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FAQs on Characoids/Tetras & Relatives Disease/Health 3

FAQs on Characoid Disease: Characoid Disease 1, Characoid Disease 2, Characoid Disease 3,
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marks on Black Neon tetra       8/10/15
Dear WWM Masters,
<Howdy Dev!>
Thanks a ton for the incredible service you provide to let us take better care of our charges. Much appreciated.
<Glad we can share>
The attached picture is of one of my shoal of 8 Black Neons. Any idea what the markings might mean? Others do not have anything similar. They are 4 months in the tank, no change in appetite or behaviour.
<Yikes.... Remove and isolate (or... destroy) the affected fish.... This appears to be an incidence of "Neon Tetra Disease" (Pleistophora, a Microsporidean)... yes, does infests other fishes.... Not curable (at this point)>
This 'warm water' tank is 30X15X12(H), about a year old, filtered by a 500l/hr HOB packed with ceramic and bioballs and a similar flow internal power similarly packed. NH3, NO2, NO3 0,0,<10; pH 7.3, kH 3, TDS 150, tankmates 6 Sterbai Cory, 4 each of Rummynose and Cardinal tetras, 1 male Pearl Gourami and a Red Lizard Plec. Crypts, Anubias, Java Fern, floating
pennywort and duckweed, Indian Almond leaves, submerged roots, river stones, caves, sand substrate. Temp is now above 30C from an Indian summer.
It has a laminar flow fan blowing across the surface, no artificial lights.
20% weekly water change, feeding from Hikari Micro pellets, sinking wafers, Ocean Nutrition Brine Shrimp plus and Spirulina flakes and Tetra bits.
Freeze dried bloodworms occasionally. I dose K2SO4 as per EI and Seachem Flourish Comprehensive and Iron.
Should I be concerned?
<Yes; and sorry to be the bearer of such bad news. DO search re the terms above... this could be another Microsporidean, Protozoan, even some worms.... As usual/always I (and I'd go far to say many other WWM Crew)
state simply what we would do given similar/same circumstances. NOT worth waiting... isolate or euthanize this black Neon>
Thanks again.
Devakalpa (India)
<Welcome. Bob Fenner>

Re: marks on Black Neon tetra         8/11/15
Dear Bob,
Thanks for the inputs. I shall act accordingly.
<Ah, good. Please keep us informed; send along your observations. BobF>

Re: marks on Black Neon tetra         8/17/15
Dear Bob,
Apologies for the delay in updating. I went the clove oil route the day I heard from you, it seemed to be the safest (but tough) option.
Since then no signs of contamination yet; the remaining Black Neons, Cardinals and Rummy Noses are doing fine.
<Glad to read>
Thanks again
<Welcome. Bob Fenner>

Tetras with white mouths (and a bit about rosy barbs)       3/19/15
Hi Crew,
I'd like to thank you once more for your previous advice, last time I wrote about a suspected case of Ich which is now resolved. I've had no more fish deaths since losing the last of the extra rosy barbs that I bought from the LFS, sadly Pinkie succumbed to his saddle ulcer in the end. I had him quarantined for the last week or so of his time, and whatever he had does not seem to have affected the rest of my fish. I still see the occasional white or clear stringy droppings from the rosy barbs but I am starting to suspect this is a result of them accidentally ingesting sand then excreting it in mucus as there are plenty of green and brown droppings too and they all seem healthy otherwise.
<Mmmm; what re water quality, foods/feeding, maintenance practices?>
Currently my 30gal tank has one head and tail light tetra, three adult rosy barbs, and all 16 of the barb offspring (ranging from 1cm to 2.5cm). I'm aware that this will be far too many rosy barbs when they grow up so I'm hoping to find a home for them in the big aquarium at work which currently only has a single small fancy (ugly) goldfish.
<Should be moved elsewhere>
I'm not sure that this will be a compatible mix though since even if 5+ barbs are added to keep them well behaved and not nippy, I think they might dominate at feeding time due to being more able-bodied and they might starve out the goldfish. Thoughts?
<All should get along w/ the GF removed>
The other option I have in mind is to set up better filtering in the backyard pond and to put some back out there. A lone
stray barb fry survived 2 weeks out there during the hottest part of summer, he was too good at hiding and got left behind when I brought the others that had hatched out there inside, so I think the pond does get enough shade to
keep the temperature down. Winters here are mild too.
<Good... barbs might live there; but not the Tetras likely in the winter>
With the threat of ich and columnaris gone I have bought four more head and tail light tetras to keep my singleton Mr. Beacon company.
<Good name>
I've been trialing different plants in the main tank and do intend to keep it heavily planted (despite the best efforts of the barbs to eat/uproot everything, I've been finding this constant battle part of the fun of keeping fish) so I am hoping the HATL tetras will be happy in the environment. The LFS does not stock these tetras so I bought them online and besides, I hoped to
avoid a known source of diseased fish. When they got here, two of them had white coloured patches on their mouths, and one of them was very sickly, limp and skinny looking.
<I see this in your excellent pix>
My initial thoughts were that they may have scuffed their mouths against the plastic bag in transit, or gotten feisty with each other since they were all together in the one small bag, and gotten injured while fighting. The bag wasn't a breather bag and the skinny fish did perk up once out of the bag and in quarantine, he hides a bit but his appetite seems okay and his belly is filling out a bit more; he could have been underfed or oxygen starved maybe but I'm a little suspicious that he could have fish TB or some other disease that could cause skinniness. I've treated them with Praziquantel so far just in case they were skinny due to worms.
<Mmm; possibly>
I'm using the tank that the baby fish used to be in, the tetras have been in quarantine for a week now and I think that in two of them the white mark has gotten smaller but noticed today that a third one has a white mouth too. I'm a little worried it could be columnaris not a wound, or a wound that got infected with columnaris.
I've attached some pictures, and also a picture of one of the friends I got for the false penguin tetra (they have their own tank now due to being too rough!) who has a similar mark. I don't know if it is just that these tetras fight or swim into things a lot; the quarantine tank that the four HATL tetras are in is too small and I know they aren't happy with the amount of space they have. I'm wary of treating with anything beyond a little bit of salt for now
and I'm just hoping after another week or two in quarantine nothing will have worsened and I can get them into the bigger tank. Anyway I just don't have the experience to tell whether these white mouthed fish are injured or diseased or both. Hope you can help.
<Not w/ the data (or lack of it) provided>
I did end up getting a RO/filter system which has a mixer tap and a TDS inline meter allowing adjustment for both drinking water and aquarium water. I still don't quite have my head around converting TDS ppm to general hardness degrees - I did read somewhere that dividing ppm by 10 will loosely approximate French degrees but then I don't know whether French or German degrees are more commonly used.
<German... the D in these measures is for "Deutschen">
I haven't had any further shrimp deaths due to failed moults since I've started using 50-70ppm water for my shrimp tank so it's definitely helping. I'm wondering whether I should still be letting my RO-mix change water stand before I use it;
<Yes I would... at least a day; better, a week>

I haven't been, because I thought that it was only necessary to allow time for water treatment chemicals to do their work but is letting water stand useful for other reasons?
<Mmm; yes.... settling, combination.... of metals, non-metals... outgassing of undesirable gasses>
I have a 20lt plastic jerry can which I store the water in, this doesn't allow much exposure to atmosphere so should this
water be agitated? Or just tipped into buckets?
<Tipped is fine, aeration/circulation better>
Ok sorry this got to be a lot longer than I originally intended! I really appreciate the time you take with educating new hobbyists like me and reading our rambling emails.
<We appreciate the opportunity to interchange w/ intelligent, sensitive folk like you>
I've still got a lot of reading that I want to do regarding Corydoras as I have decided I'd like a biotope tank rather
than putting them in the community and making them compete with greedy barbs, and I think it would be easier to manage water softness and ph if I start again and do things differently in a new tank.
Thanks once again and I hope you have a great day.
<Welcome. Bob Fenner>


Re: Tetras with white mouths (and a bit about rosy barbs)      3/20/15    /Neale
With regards to the barbs occasional odd dropping, they are fed once daily or twice if I don't have time to watch them in the morning. If I am in a hurry they get a quick pinch of flake and then I take a bit more time in the evening feed to watch how much they are eating.
<Fine. Barbs are omnivores that will eat algae, some plant matter between "proper" meals.>
I have some frozen community blocks which contain both meaty and plant materials, I usually give this two to three times a week (slicing off a small amount and feeding little by little trying to avoid over feeding). I have some Spirulina sinking pellets (also contains other ingredients) that I bought for the shrimp but proved to be very popular with the barbs, they will carry the pellets around spitting them out and sucking them up again, gradually working on them until they soften up.
<Quite so, and an excellent staple for your fish... good nutrition, plenty of exercise, economical. My Cherry Barbs are fed these alongside the Limia they cohabit with.>
I crush some up for the younger fish but they seem to manage okay on full sized pellets, worrying at them until they break into smaller bits. I have some meatier pellets, with a higher protein content but they are not as popular so I don't feed those very often.
<Indeed. These fish are omnivores, and plant material is a significant part of the diet of most/all barbs in the wild.>
They get smushed up frozen peas, thawed and peeled, every few days which they love. If I find a patch of snail eggs I will knock it off the glass and the female adult barb in particular loves munching on those.
Occasionally I net some mosquito larva from either the pond or the snail tub and these make a popular snack.
I believe they have eaten some of the Ramshorn snails that were in their tank, there are a growing number of empty shells visible on the bottom, and they definitely rip at the Java moss, Hydrilla, Rotala, and Hydrocotyle plants constantly. I'm pretty sure they ate 90% of the fissidens moss I added too, and almost all of the hair grass is gone too now that I think
about it. I was worried at first that they were doing this because I wasn't feeding them enough but they were still doing it when I tried feeding them twice a day which I decided was too much. I think if they like eating fresh plants then they should be allowed to eat fresh plants so I've been growing more Hydrilla in a tank outside for them since that's the one they stripped to bare stems first of all.
<Indeed. Try floating Indian Fern and Amazon Frogbit, two favourites with many barbs.>
I don't often see the tetra eat, he hangs back while the barbs feed so I always attempt to get a pinch of flake to his part of the tank. He doesn't like me scrutinising him though and moves front on so that he's hard to see. He does get interested in the frozen food and will test and spit out various particles of it until he finds one that he likes, I'm hoping he gets a bit more confidence once his fellow tetras join him, I've been feeding them a small amount of flake daily and they get quite excited at feeding time so I think in a group his instincts will kick in if he sees a lot of feeding action going on around him.
<Tetras are frequently more carnivorous, especially the smaller ones Neons, Penguins, various Hyphessobrycon species and so on. They often enjoy Daphnia and the like. On the other hand, do bear in mind some tetras are much more retiring than Barbs. Put another way, many South American tetras come from blackwater streams with very little productivity. They've evolved to expend as little energy as possible between meals. Barbs typically come from ponds and streams with much more productivity and a lot more for them to eat. They've evolved to be more "busy" and expend their energy in all sorts of foraging and social behaviours. In other words, tetras wait for food to come to them, while barbs seek it out and if necessary push competitors away. Funnily enough, those barbs from blackwater streams (like Pentazona Barbs) are much more like Neons and other tetras in personality.
In any event, if you understand the environment the barb or tetra species come from, cohabiting different species from among them will work better.
Tiger Barbs are bolshy, so mixing with pushy characins like Black Widows makes sense. Rosy Barbs are subtropical to boot, so you'd choose only low-end tropical tetras for life with them, perhaps Buenos Aires Tetras.
Does this make sense?>
I haven't measured my water parameters for a while but for a long time I was getting pH steady at 8 (despite driftwood and almond leafs) ammonia 0, nitrite 0 and nitrate 5-10. I do weekly water changes and fortnightly rinses of the gunk from the filter. I try weekly to vacuum the gravel in the gravelly parts of the tank and skim the surface of the sand in the sandy parts of the tank but I don't know how effective a job I do. I always see gunk being sucked up the tube but everything looks even messier than when I started once I've tipped the new water in.
<Sounds good. Cheers, Neale.>

Tetras with white mouths (and a bit about rosy barbs)    /Neale        3/21/15
Hi Crew,
I'd like to thank you once more for your previous advice, last time I wrote about a suspected case of Ich which is now resolved. I've had no more fish deaths since losing the last of the extra rosy barbs that I bought from the LFS, sadly Pinkie succumbed to his saddle ulcer in the end. I had him quarantined for the last week or so of his time, and whatever he had does not seem to have affected the rest of my fish. I still see the occasional white or clear stringy droppings from the rosy barbs but I am starting to suspect this is a result of them accidentally ingesting sand then excreting it in mucus as there are plenty of green and brown droppings too and they all seem healthy otherwise.
<Smooth silica sand should be fine... but anything abrasive or sharp, like some of the glass-byproduct sands (Tahitian Moon Sand for example) could be risky.>
Currently my 30gal tank has one head and tail light tetra, three adult rosy barbs, and all 16 of the barb offspring (ranging from 1cm to 2.5cm). I'm aware that this will be far too many rosy barbs when they grow up so I'm hoping to find a home for them in the big aquarium at work which currently only has a single small fancy (ugly) goldfish. I'm not sure that this will
be a compatible mix though since even if 5+ barbs are added to keep them well behaved and not nippy, I think they might dominate at feeding time due to being more able-bodied and they might starve out the goldfish. Thoughts?
<It can work, in big tanks with robust Comet-type Goldfish and decent sized schools of Rosy Barbs. But fancy Goldfish are less able to keep out of trouble. It really isn't predictable. Worth trying but keep a Plan B in case it doesn't work out.>
The other option I have in mind is to set up better filtering in the backyard pond and to put some back out there. A lone stray barb fry survived 2 weeks out there during the hottest part of summer, he was too good at hiding and got left behind when I brought the others that had hatched out there inside, so I think the pond does get enough shade to keep the temperature down. Winters here are mild too.
<Rosy Barbs are subtropical and could thrive down to about 15 C, but below that would be risky.>
With the threat of ich and columnaris gone I have bought four more head and tail light tetras to keep my singleton Mr. Beacon company. I've been trialing different plants in the main tank and do intend to keep it heavily planted (despite the best efforts of the barbs to eat/uproot everything, I've been finding this constant battle part of the fun of keeping fish) so I am hoping the HATL tetras will be happy in the environment. The LFS does not stock these tetras so I bought them online
and besides, I hoped to avoid a known source of diseased fish. When they got here, two of them had white coloured patches on their mouths, and one of them was very sickly, limp and skinny looking. My initial thoughts were that they may have scuffed their mouths against the plastic bag in transit, or gotten feisty with each other since they were all together in the one
small bag, and gotten injured while fighting. The bag wasn't a breather bag and the skinny fish did perk up once out of the bag and in quarantine, he hides a bit but his appetite seems okay and his belly is filling out a bit more; he could have been underfed or oxygen starved maybe but I'm a little suspicious that he could have fish TB or some other disease that could
cause skinniness. I've treated them with Praziquantel so far just in case they were skinny due to worms.
<Fish TB is difficult to diagnose and impossible to treat. It's less contagious and more like an epidemic that breaks out when fish get stressed (diet, poor water quality, lack of oxygen, etc.). So I tend not to worry about Fish TB but instead focus on optimising living conditions for the fish. Usually "mystery deaths" either sort themselves out or else all the vulnerable fish die. Adding medications randomly is a bit hit and miss, and while PraziPro isn't particularly risky, do be careful about medicating
without diagnosis.>
I'm using the tank that the baby fish used to be in, the tetras have been in quarantine for a week now and I think that in two of them the white mark has gotten smaller but noticed today that a third one has a white mouth too. I'm a little worried it could be columnaris not a wound, or a wound that got infected with columnaris. I've attached some pictures, and also a picture of one of the friends I got for the false penguin tetra (they have their own tank now due to being too rough!) who has a similar mark. I don't know if it is just that these tetras fight or swim into things a lot; the quarantine tank that the four HATL tetras are in is too small and I know they aren't happy with the amount of space they have. I'm wary of treating
with anything beyond a little bit of salt for now and I'm just hoping after another week or two in quarantine nothing will have worsened and I can get them into the bigger tank. Anyway I just don't have the experience to tell whether these white mouthed fish are injured or diseased or both. Hope you can help.
<Well, the photos look more like fighting damage, perhaps a bit of Finrot or Columnaris thrown in. Another option: swimming into solid objects (like the glass) when alarmed. So for this one turn the lights on more carefully and see what happens. So far as fighting goes, watch your fish, add more of each species to dilute aggression (if an option) and medicate as per Finrot
and Columnaris.>
I did end up getting a RO/filter system which has a mixer tap and a TDS inline meter allowing adjustment for both drinking water and aquarium water. I still don't quite have my head around converting TDS ppm to general hardness degrees - I did read somewhere that dividing ppm by 10 will loosely approximate French degrees but then I don't know whether French or German degrees are more commonly used. I haven't had any further shrimp deaths due to failed moults since I've started using 50-70ppm water for my shrimp tank so it's definitely helping. I'm wondering whether I should still be letting my RO-mix change water stand before I use it; I haven't been, because I thought that it was only necessary to allow time for water treatment chemicals to do their work but is letting water stand useful for other reasons? I have a 20lt plastic jerry can which I store the water in, this doesn't allow much exposure to atmosphere so should this water be agitated? Or just tipped into buckets?
<Bob's a big fan of overnight "resting" of water, ideally with an airstone, but not essential. I'm less fussed, and just avoid changing huge amounts of water. Basically, if you just change 20-25% of the water at a time, and use a water conditioner, you shouldn't need to worry too much about resting the tap water. Freshwater fish are very much more adaptable than marine fish. Think about rain falling into a pond.>
Ok sorry this got to be a lot longer than I originally intended! I really appreciate the time you take with educating new hobbyists like me and reading our rambling emails. I've still got a lot of reading that I want to do regarding Corydoras as I have decided I'd like a biotope tank rather than putting them in the community and making them compete with greedy
barbs, and I think it would be easier to manage water softness and ph if I start again and do things differently in a new tank.
<Possibly. I'm a big fan of sticking with the water chemistry you have, and choosing your fish accordingly. That said, a 50/50 mix of RO water and liquid rock tap water should produce a happy medium that suits most community fish.>
Thanks once again and I hope you have a great day.
<Most welcome. Neale.>
Tetras with white mouths (and a bit about rosy barbs)       3/21/15

Hi again Crew!
Thank you for your replies Bob and Neale. My heart says that I should move the head and tail light tetras into the main tank to give them space and stop them from squabbling or bumping into things, but my head says to give them another week of quarantine to see how their mouth lesions develop.
I slept on this idea and this morning while one HATL tetra is still without mouth issues, two of the other three look worse and the white patches seem to be protruding more than they were yesterday. Although, having said that, I did use a brighter light so that I could see them better, maybe the lesions were like that all along and I just didn't see - normally they have half the tank in shade c/o a black plastic garbage bag and the other half lit by a strip of dim LEDs. I don't really think the lesions look fluffy, more so a bit ragged like the edge of some peeled skin in places, and warty in others. However this fluff free finding doesn't relax me at all, as Pinky's back ulcer was never fluffy either and that evolved from a small lesion to a large fatal ulcer over the Christmas/New Year break (I didn't have anything available except topical treatments until it was too late). I
don't really want to give infection a chance to set in again, but I am mindful also that these are different fish, from a different supplier, in a different tank, with different looking lesions that are in a different location on the fish, so I shouldn't expect a similar outcome to last time!
I want to wait a bit longer and observe them tomorrow with the same bright light so that I can get a real idea if there is any progression. I do have tetracycline (Bio-tet) or Metronidazole (generic looking yellow tablets) available now for if the lesions worsen, although I'm not sure if I want to treat all the fish, or only the ones that are showing visible lesions.
<I do think these mouth lesions are either plain vanilla dead tissue from fighting or crashes into solid objects, or else incipient Columnaris.
Either way, treat with a suitable antibiotic, while also review conditions in the tank.>
An observation on a different front, I would be hard pressed right now to pick out which of these fish was the skinny sickly one from a week ago. All of them have good colour and healthy looking bellies now. I am really looking forward to seeing them school together in the big tank once they are done in quarantine! I have discovered that my dad's compost heap has
Whiteworms in it as well as the big pink compost worms so I want to set up a new clean worm culture for some tasty occasional snacks for the fish, which I hope the tetras will like.
<Sounds a great idea.>
Speaking of which, the other fish haven't been eating my Ramshorn snails at all! I found three snails fatally jammed in the filter inlet grille today.
I am guessing as the grille becomes more clogged with plant matter it becomes a tempting place to graze for the snails but the increased suction as they clear a blockage pulls them in to the inlet pipe and traps them there, where they die since their shells can't follow. I have seen snails "hanging around" the inlet pipe before but didn't realise this was happening. The filter pipe has probably been slurping snails out of their shells all along as the barbs seem content to bite their eyestalks off then
go back to ripping at the plants. I've adjusted the sponge that I put over the grille so that only the most suicidal snails will be able to force their way in there, and I will just have to remember to rinse the debris out more often.
<Hmm... some folks would endorse a filter with snail-killing properties...>
I've decided that it will probably be more humane to leave the fancy goldfish in peace in the aquarium at work and to get a nice pond filter going to allow rehoming the excess rosy barbs outside, I probably wouldn't be able to provide adequate supervision to stop any possible mayhem that could occur with the work goldfish. It does get a smidge under 15 deg C here over winter, but the pond should get winter sun.
<Definitely worth trying, I reckon.>
If I can't work something out using either a solar pond cover or something similar to harness solar warmth, I can always bring everyone back inside in a temporary plastic crate for the coldest months.
<Both approaches make sense. Cutting down wind chill in winter with, say, a bamboo cover of some sort might work nicely. On the other hand, bringing in some or all of the Rosy Barbs before the coldest months start can work great, too. Have known many aquarists do this, even in places like Ohio where the summers are nice and hot but the winters rather severe. They had fish that bred prolifically during the summer, but snuggled up indoors for the winter. It's an ideal approach if you're careful, and I found Corydoras for example easily bred this way.>
Thanks again for helping me sort through these problems!
<Cheers, Neale.>

Re: Tetras with white mouths (and a bit about rosy barbs)   3/29/15
Hi Crew! I hope all is going well with you.
<Certainly is.>
A quick update on the tetras: the mouth lesions shrank away to nothing on two of the head and tail light tetras while the remaining one is almost gone.
<Good to hear.>
It's starting to get cooler overnight here so I decided it was time to transfer the new ones to the main tank as the quarantine tank doesn't have a heater yet - prior to now the water temp has rarely been under 26 C. The new tetras settled in straight away and Mr. Beacon joined up with the group as soon as he noticed them. As far as I can tell from both the size
differences and the swim bladder shapes, Mr. Beacon is in fact correctly named and is male with a pointy swim bladder, while the new tetras are a little larger, a little more lightly coloured, with bluntly rounded swim bladders, and all female. The largest two females seem to push each other around a bit and vary between ignoring Mr. Beacon, and chasing him away. He
seems to spend a quarter of the time hiding, a quarter of the time trying to sidle up to a female while she ignores him and swims away, and the rest of the time they hang together in a loose school with no hassles.
Perhaps without another male to compete against, the females find him completely unimpressive?
<Or they're sexually immature, or a different lookalike species.>
In any case it's a big improvement for him activity wise, and i am pretty sure he is a bit bolder at meal times. The tetras seem to love the Spirulina pellets just as much as the barbs do, and grab one and hold it in their mouths until it softens up so that no one can steal it from them. They occasionally pop the pellet out and balance it in their lips before quickly sucking it back in, which looks really cheeky, but I am guessing they are just checking it for softness.
<Fish can't chew.
<<Mmm; many can. RMF>>
If they need to break food down, they often crunch it as best they can, spit it out, suck it back in, and repeat as necessary. Since water buoys up food particles for a while, keeping them close to their mouths, this isn't too inefficient.>
I'm glad you talked me out of taking any drastic measures with regards to treating the mouth lesions, it's hard to stay patient when the Internet is full of horror stories of apparently healthy fish who turn into sideways floating piles of white fuzz overnight, etc, but "wait and see" did produce the best result, allowing the fish to fix themselves.
<Pretty much.>
We had a near miss in the work aquarium, jammed/busted impeller in the filter pump turned it into a heater. I noticed the filter wasn't running right at the end of the day and the water was warm enough to bath in! Must have been cooler towards the bottom of the tank otherwise I don't know how the poor goldfish didn't cook. I don't think he would have made it if it
was left like that overnight. Well it turned out for the best for the goldfish, the replacement filter doesn't have anywhere near as strong a flow rate so he doesn't get blasted around the tank any more like he used to, but it goes to show the tank isn't in a position where it gets seen often enough for people to catch any problems. I only saw it because I was being particularly lazy and looking for ways to waste time, under normal circumstances it wouldn't have been seen until the next day. So I am now even more convinced not to take any rosy barbs to go in that tank. The office area is going to be overhauled soon so if the new layout involves the fish tank being in a better place I might change my mind.
<Quite so; sounds like a good project to think about some time. Generally yes, the best place for a fish tank is a reasonably busy place where people can see the tank and be mindful of its care, plus somewhere it's easy enough to get buckets of water to and from. Direct light and heavy footfall aren't helpful though.>
Thanks again!
<Good luck, Neale.>
fish + chewing          3/30/15

> Hi Bobster!
<Hey Neale>
> Chewing is, zoologically speaking, confined to mammals. You need molars and cheeks to do it, plus the right sort of muscles, nerves and enzymes.
<Mmm; let me see re a ref. here: I see that they don't!
"Do fish chew their food? Fish do not chew their food in the same manner we do. Many carnivorous fishes (meat eating) use their sharp teeth to capture and hold prey while swallowing it whole or in large pieces. We use teeth to grind food into tiny pieces, and then we swallow. Bottom dwellers such as rays have large flat teeth that crush the shellfish they eat. A number of herbivorous fishes (grazers) grind their food in a manner similar to humans. However, the tooth-like grinding mills are located in the throat rather than in the mouth, and are referred to as pharyngeal ("phar-yn-geal") teeth. ">
> What a few fish do is grind (see for example coral-eating parrotfish). So far as I know, they don’t have the tongue and cheek muscles needed to position and reposition the food inside the mouth while they’re doing it. They certainly don’t moisten the food (hardly necessary!) and neither do they apply enzymes produced by the mouth to start digestion. Subsequent processing happens in the throat of course, with the pharyngeal teeth. But that isn’t chewing either.
> Cheers, Neale
<A matter of definition on my part. Cheers, BobF>
Re: fish + chewing          3/30/15

Quite so. But neither you nor I would call ourselves zoologists if we didn’t have a tendency towards pedantry now and again!
<A trend I try to be aware of and resist>
So, the podcast was pretty fun. Mentioned WWM a few times, but I’m sure an “all Bob, all the time” episode would be better!
<Am very sure this is not the case>
Cheers, Neale
<And you; BobF>

Minor Serpae Tetra fin rot?     11/2/14
Greetings. I have a 55-gallon aquarium that we set up 2 years ago & has been stable and disease-free. Water parameters are: ammonia = 0, nitrite = 0, nitrate = 30, phosphorous = 0. I do a water change every week. We have live plants (water sprite wisteria). The inhabitants are 2 Bristlenose Plecos, 8 black-skirt tetras, 8 white-skirt tetras, 11 minor Serpae tetras, and about 6 apple snails. The Serpae tetras were introduced about 2 weeks ago and my quarantine tank currently is housing some baby Gold Gouramis, so
I chose not to quarantine them. I know I should have, but I have never had any problem with the tetras from this source. A bad decision on my part, but anyway, may I explain the problem to you...?
<Fire away.>
Oddly enough, the other fish in the tank seem to be still healthy and unaffected by this disease bothering the serape tetras. It is the strangest thing I have ever seen. The first sign is a very pale area where the dorsal
fin meets their body. It's very clearly delineated and easy to see against their red-orange background. Soon after that, the dorsal fin degenerates and the fish seems to die within a day or two after they reach that stage.
They don't seem swollen and neither do they show any other signs of illness. I have never seen fin rot behave like this or fin rot that just affects one species of tetra. Today, I got some API Triple Sulfa and am
planning on giving them the entire course of treatment as directed by the manufacturer. Do you think that I am on the right track here? Please advise and thank you so much for your time and any comments you may have for me.
<Serpae Tetras are notorious fin-nippers, so one explanation is that they're fighting within the group (which they do, especially when feeding) and damaging one another. When feeding they have a feeding frenzy
behaviour, but will also bully weaker specimens, even killing them. Usually they attack other fish too, but the Black/White Skirt Tetras (both Gymnocorymbus ternetzi) are pretty pushy, fast-moving little fish
themselves, and may be holding their own just fine. Gouramis, though, are easy targets so I wouldn't mix them. This said, it is rare for Finrot to kill fish within a couple days. Adding more Serpae tetras might help, by
spreading out any aggression, but before doing that you'd want to observe the Serpae Tetras and see if they're chasing or nipping each other. If they are fighting, adding a few more could be a good move. Alternatively, you might simply have a "bad batch" of Serpae Tetras, in which case medicating for Finrot might stabilise things, giving you time to see if they can be saved. If the fish get better, then no harm done. If they eventually all die, I'd recommend not buying Serpae Tetras again. Although cheap and usually extremely hardy, they aren't well behaved fish, and there are better alternatives such as Red Phantom Tetras out there.>
<Cheers, Neale.>
Re: Minor Serpae Tetra fin rot?    11/15/14

Greetings. Well, I treated the entire aquarium with API Triple Sulfa for four days and then observed the aquarium for several days and the mysterious problem of the bacterial infection with the Serpae Tetras seems to have been eradicated. All the fish look very healthy.
I have been watching them closely for fin nipping and have only seen a limited amount of chasing amongst the Serpaes and a few isolated incidents of them bothering the black & white skirt tetras who, as you previously
stated, can give it back to them even better than the Serpaes can dish it out.
<Often the case. Both species are "fin nippers" but Serpae Tetras tend to be more persistent and vicious, whereas Black Widows generally behave themselves if there's enough of them.>
I haven't seen them bothering the gold gouramis, who can be rather pugnacious also if they choose to do so.
<Males, yes; females less so, if at all. Also, as they age, they slow down a lot, making them easier targets, so do keep an eye out for them.>
I will watch the gouramis closely and move them to another aquarium if necessary. I will keep watching the Serpaes for aggression. I have not found anyone yet who has any idea exactly what this strange infection was,
but the guy at PetSmart said that the others that came in in that particular group had to be treated with antibiotics as well. Anyway, just to let you know what the outcome was with this incident. Thanks for the heads-up on Serpae aggression. I did notice that they are on nippy fish.net where they seem to be known as the culprit in many a fin-nipping incident.
<Indeed. Excellent fish in terms of colour, size, and usually hardiness.
They were extremely common fish in the aquarium hobby during its earlier phase. But nowadays are not as popular. Unfortunately some retailers give them alternate names, making it easy to buy them by mistake. Red Minor Tetra, Jewel Tetra, Hyphessobrycon eques, Hyphessobrycon calistus and Hyphessobrycon serpae are some of the names you'll see.>
Thanks again for your advice.
<Welcome. Neale.>

Payara help - parasites        2/3/13
Hi Crew, How are you?
<Fine; but you've surpassed (way) our limit for file size>
My name is Daniel and I'm facing a strange problem with my characins fishes.
It seems like a parasite problem but I'm not sure of which kind.
The symptoms are: 1- Little white spots in fins and eyes. 2- Eyes sometimes clouded but not the entire eye! Just a portion of the cornea. 3-Some thin "things" like a baby's hair attached to the fish.
My fishes are eating well. They aren't rubbing against nothing. All symptoms seems to be cyclic and the cycle seems to be fast (days to weeks).
I took that pics from the eye of my H. tatauaia yesterday, today that eye is almost completely normal...but the other one turned cloudy today.
<Mmmm... something going on here. IF only one fish, perhaps just a physical trauma>
Pics attached.
*Note that besides the "large eye spot" there is some small too.
*Note the "thin hair thing" in the back of the A. falcirostris.
<Have magnified... is this a crustacean parasite? Is it some sort of artifactual material?>
My water parameters: no ammonia, nitrates..
<I take it you mean nitrites (with an 'i'). What are your nitrates?>

I really don't know, temp 28-29 Celsius, Ph 6.0, WC every week, they eat frozen fish (entire fish not just fillet).
What is this? How can I treat?
<Can't tell from the data provided... I wouldn't "treat" at all; but advance the maintenance (water and media change outs)... and stay observant>
Thank you and sorry for my bad English.
<No worries; I understand you and that/this is all that is important. Bob Fenner>

Looks like an embedded fin spine to me.
Re: Payara help - parasites        2/3/13
Hi Bob, thank you for your reply!
I don´t have any trace of nitrites right now.
<Good... and the NitrAte? [NO3]?>

The problem is happening in at least 5 of my fishes. It seems to be very cyclic. In 48 hours patches appear in the eyes of the fishes.
<Most likely environmental then; not pathogenic>

 First they appear as cloud eyes and after sometime they turn white "concentrated". After a day you can see very "thin things" (thinner than a hair) leaving the eyes or fins of the fishes and the eyes became clear for 2 or 3 days and when you think that everything is ok, it happens again. It is absolutely weird.
The Payara picture represents the concentrated phase (white).
I will resend you a picture with less pixels.
Thank you
<The usual massive, consecutive days water changes; use of activated carbon, PolyFilter or equivalent. BobF>
Re: Payara help - parasites        2/3/13

I'll check my nitrates tomorrow, my test is "out of date". Normally I do 50% WC every 7 days. I 'll follow your advice and do it more frequently.
<I encourage you to add a few tablespoons of baking soda (Sodium bicarbonate) each change as well... to aid nitrification, add a bit of alkaline reserve. See Neale's article on same on WWM>
By the way, I'm running this system (140 gallon tank) with PolyFilter, carbon and 40 liters of Siporax
<Ah yes; the Siporax might well remove most all NO3>
My fauna: 1. Hydrolycus tatauaia, 3 Acestrorhynchus falcirostris, 3 Boulengerella maculata, 1 Crenicichla tapajos II and 1 Potamotrygon hystrix
Thank you again Bob!
<Welcome. B>

Sick Tetras?      8/27/13
Hi guys,
Starting out with details and parameters:  I have a 30 gallon tank that I set up almost three months ago.  A month and a half a go, I got 3 Neon Tetras and a Ghost Shrimp.  Two of the Tetras died very shortly, so I waited two weeks, checking parameters, and then got two more Tetras.  They have been fine until about four days ago.
<I see. Well, the quality of most farmed Neons is not good, and "Neon Tetra Disease" (or diseases plural, there's some debate on this) can be particularly difficult to deal with. Once sick from this disease, Neons are highly contagious but difficult (usually impossible) to treat. That said, not all Neons die from Neon Tetra Disease, so be open minded, and do all the usual things you do when fish get sick, in case there's another reason they're ailing.>
My Nitrates and Nitrites are at 0, but my ammonia is at .25ppm. My tap water reads for over 1ppm straight out of the tap, so I have been using Prime and I get false readings for my ammonia concentrates.
<Possibly, but be open minded and review filter capacity, feeding, stocking, etc.>

I did a 25% water change two days ago, and before that, the ammonia read at 0ppm.
I am having trouble identifying a disease that my Tetras seem to have.  It started out with one Tetra hiding instead of schooling with the others.
<Is what Neons do when stressed, though is often associated with "Neon Tetra Disease". Such fish should be promptly removed, and to be honest, euthanised (I recommend the Clove Oil method as cheap, easy and humane).
You see, Neon Tetra Disease is extremely contagious, and medicating isn't possible. If you suspect there may be another explanation, you could isolate the Neon in a hospital tank and treat for Whitespot, Finrot or whatever, but unless you're 100% sure that your fish doesn't have Neon Tetra Disease, I'd always medicate in a hospital tank, not in the display tank.>
When he came out of hiding to eat, I noticed a white spot on his lip.  I got some Jungle "Ick Guard" and have been using it per the directions, as well as adding aquarium salt to my tank.  Over the next day or so, the sick fish got worse and the two others began to come down with the same symptoms.  I have been using the Ick Guard for 4 days now, and the fish are
not getting better.
<Oh dear.>
Today, I noticed that my Ghost Shrimp had white spots on him, as well (he disappeared for 3 days and I almost thought he was dead).  I Googled to see if invertebrates can get fish parasites, and the general consensus was that they cannot.
<Correct, but many fish medications are lethal to shrimps, particularly anti-Whitespot and similar medications that contain either copper or formalin. Always remove shrimps when medicating, or else remove the sick fish to a hospital tank.>
(Btw, he molted about a week ago, and one site said spots could be a sign of molting - would he do it again so quickly?)
<May well do.>
Between the shrimp getting spots and my fish getting worse instead of better, could the disease not actually be Ich?
<The photos are too blurry to be sure, but the fish look to me like they might have either Finrot or Whitespot/Ick, it's just not clear to me.
Whitespot looks like the fish fins and body have had salt grains stuck to them. It's very distinctive. Finrot erodes the fins usually from their edges inwards, and the fins often go cloudy, sometimes pinkish, as the fin membranes die. Again, quite easy to identify. It's possible for a fish to have both, by the way, and they're both common problems in newish tanks
when un-quarantined fish have been recently added and/or existing fish exposed to poor water quality.>
Is there another disease that they might have, or is it just a coincidence that the shrimp also has white spots?
<The latter; shrimps can't get Whitespot. For sure they might suffer in some way from poor water quality, but Finrot as such isn't going to happen.
Shrimps usually just die when stressed.>
I have included pictures, but they aren't terribly great because everyone in the aquarium moves so fast.
<Quite so. Try using a net to gently hold a fish against the glass. Use a tripod (or a friend with steady hands) to hold the camera.>
In the pictures, I have tried to point out spots where you might be able to see the white spots. Thanks in advance for any help, you guys are an amazing source of knowledge, and I have learned so much from your site.
<Hope this helps, Neale.>

Lump on cardinal tetra.       4/25/13
Hello WWM crew,
I need your expert advice with one of my cardinal tetras. It has what looks like a lump on the area under its gills. I attached two pictures I hope you can see them.
<No photos attached.>
It started as a white patch a few days ago and now it looks almost transparent with what it looks like a white worm inside. I have not tried any medication yet.
<Could be several things. Is the "white worm" moving? How has it developed in the past 24 hours?>
He is eating ok and schooling with the others. I have 5 other cardinals and 1 Amano shrimp in the tank which are all looking good. The tank is a 12 gal planted with water parameters of: ph 7.5, kH 6, gH 7, ammonia 0, nitrite 0, nitrate 5, temp 82. I use RO water buffering with baking soda to 6 kH and adding some SeaChem flourish for the plants once a week when I do the 30% water change. I also have a diy co2 system.
I've had the tank set up for about 3 months. I did the fishless cycle successfully thanks to some great advice from the awesome Bob Fenner. And added the fishes and shrimp about 2 months ago. No problems so far except for this issue now. If you know what it is and how to treat it if there is any treatment for it. Any comments and advice will be appreciated.
<Without the photos it's dangerous to guess at treatment. It matters a lot if the "white worm" is a parasite or just something that looks like a worm but is not. That is to say, is there a parasite involved? What I will say is that this tetra should be quarantined ASAP to minimize the chance of spreading it to other inhabitants.>
Thank you Fremi.
<I'm afraid not much help at the moment, but do try to attach the photos again. The will be very helpful. - Rick>

Re: Lump on cardinal tetra.     4/25/13
Hello Rick, 
<Hi Fremi>
I attached two pictures, I hope they come through. 
<Yes, and the photos show the lump as clearly as can be expected.>
There has been no change in the past 24 hrs it is still the same. The worm is not moving it just looks like a s shape white worm almost like a hair inside a water blister.
<It's very strange indeed.  I haven't encountered a problem like this.
Nothing similar appears in my manual of fish health either, which leaves us still guessing.  My guess is that it is either parasitic or bacterial similar to a lesion, but of the two I am inclined to think parasitic. I would definitely quarantine this fish, which helps prevent spreading to other tankmates. It's also easier to medicate in a small tank.  I've had success against parasites with API General Cure and also with Prazi-Pro,
but they don't treat exactly the same things.  If it were me, I'd be inclined to give General Cure a try, but let's see if anyone else recognizes this. Taking blind shots with meds is stressful for the fish. 
Bob and/or Neale, have either of you seen this before? - Rick><<I have; many times... Sporozoan/Microsporidean likely; not treatable... and yes, catching to conspecifics. Might be of use to have a read here:

Re: Lump on cardinal tetra.      4/26/13
<<<<I have; many times... Sporozoan/Microsporidean likely; not treatable...
and yes, catching to conspecifics. Might be of use to have a read here:
<Bob, thanks for the input and link. Fremi, there we are. Please read the link Bob provided (as I shall), and do quarantine that fish before you have more of this problem You can still take a stab at treatment but as indicated, success is doubtful.  - Rick>

Mystery ember tetra illness     8/25/12
<Eight megs of poor pix... why don't people follow directions?>
Dear Wet Web Media Crew,
I'm a long time fish keeper, and run a small maintenance service business.
So I've seen my share of illness and have my own tools for dissection etc on hand and can usually pin down most common illnesses and pests.
<Ah yes>
Yet, I've an issue with my ember tetras in my home display tank that has me baffled.  I have 9 embers, 3 panda Cory, 2 albino Cory and 4 three-line Cory in a 60L (15G) planted tank.  It's been running years with zero issues and great plant growth.
However, i seem to loose <lose>  an ember every few months. I've lost 3 so far.  As they are somewhat transparent, I've notices the occasional tetra with black masses in various points around the internal organs.  They sometimes occur behind the gill, sometimes above the swim bladder, sometimes near the kidney etc, and once there seem to spread slowly in the body.  The affected fish is quite fine, active, eats well, good colour for 2-3 months, and finally looses colour, begins breathing rapidly, and at last keels over in about a week or so.  It seems like some sort of internal parasite which causes little trouble until the load becomes too much, and then the fish succumbs.  Most of the other fish are disease free, and it seems usually one is affected at a time.
I've tried catching infected animals to remove them (and hopefully the disease) from the tank, but in a heavily planted set up it's near impossible.
I've not tried anything for treatment save excellent diet and water quality as i dislike treating with meds unless I'm certain what I'm dealing with, and often I've found good care often helps most fish resolve problems themselves.  Tank parameters are: nitrates at 10-20ppm, 0ppm ammonia & nitrate, pH 7.2, GH 4 degrees, KH 3 degrees.  Weekly 30% water changes.
Tank is dosed daily with Flourish Excel, and every 2nd day with liquid ferts (Aquamaster brand).
I've attached a few pics of the latest case.  They don't seem to be nodules, flukes etc, so not sure if a very tiny helminth, bacterial or protozoal mass.
Any help is greatly appreciated.
Kind regards
<Sounds/reads like one of the many "mysterious" Microsporozoan, Microsporidean infections; quite common w/ imported Characins from the wild. Do see Ed Noga (the second ed. if you can... avail. as an e-book am given to understand) re.
Bob Fenner>
Acumen Aquatics - Premium Fin Safe decor, aquarium installation, aquascaping, assistance & service.
Canberra, Australia

both cropped

Re: Mystery ember tetra illness 8/25/12
Hello Bob,
Thank you for the very speedy reply - been researching around as just found that book last night!  I've got the worst case caught and now in quarantine.  When it passes (it's looking past the point of no return) i will check it under the microscope and refer to the book. I have The Manual of Fish Health by Chris Andrews et al and a few others, but not too much
info on Microsporozoans etc.
<I wish I had more, better news to report. As far as I'm aware there is/are no cure/s for...>

Thanks for the good book reference.
Kind regards
<And you, BobF>
Re: Mystery ember tetra illness 8/26/12

Hi Bob
<Salve Lea>
That's sad news, but again appreciate your expertise.  I did find one site pertaining to microsporidia which suggested possibly Metronidazole - though not specifically for fish.
Here's the link if you are interested, it's from Stanford.
<I thank you for this; these infestations can be... persistent, and heartbreaking... in slowly killing off all specimens. Providing "Ideal Circumstances" environmentally, nutritionally... seems to help, slow down the rate of incidence, attrition>
I will continue to keep water quality and diet excellent, and i can only hope the shoal shakes it with their own immunity in time.  I will try adding garlic to boost immunity, and have also given a treatment of a combo formalin, malachite green & Acriflavine to maybe assist in interfering with any water-borne spores (i consider this combo a good broad-spectrum against various gram positive, negative, Protozoans and fungi, which Microsporideans are in the same family). A long shot but i feel it can't hurt too much at this stage.  I will see how this goes after a week, and if no improvement i will discontinue and try Metronidazole in a week or two after the former meds have cleared.  I am always wary of over-medicating and stressing my fish.
<You are wise here>
Thanks again
<Certainly welcome. BobF>
Re: Mystery ember tetra illness     8/27/12

My pleasure Bob - i hope it is of some use.  I was a biologist in my former iteration, and i enjoy research and problem solving to this end.
Speaking of which, i euthanised my ill tetra last night and performed an immediate autopsy.  I found a large infestation of very tiny black particles approx 0.5 mm (barely visible) which seemed slightly oval under my 5x lit magnifying glass. They were not within nodules (like presentations of nodular disease images shown in the Chris Andrews book), but rather simply clustered together.  They were present in the stomach, around the liver, in the kidney, and up behind the brain to the extent that pop-eye was a final symptom. I'm picking up a microscope next week to investigate further and have saved samples of some of the heavily infected sections in water in the freezer (hopefully the main structures will not be ruined when i thaw).
<Better to use a preservative...>
 I'm am wondering what else they could be, as they seem to infect like Microsporideans, but these black specs are far to large (given i can see them just with the naked eye).  Maybe some internal protozoal infection, or a very small internal fluke? I guess it may also be possible that these are simply actual fish cells which have turned black by engorgement of smaller parasites.
If you wish I'll keep you posted and send some images once i collect my microscope.
<I thank you for this>
As you say, it is heart-breaking as that last thing i wish to do is tear down this beautiful planted tank.  Several of the tetras seem unaffected, but that's not to say they are not latent carriers.  Will monitor and let you know.  Also just found that Metronidazole is not available in Australia unless you seek out a vet, so it may take a little time to find a specialist i can obtain some from.
<Yes; the case there is common around the world>
Have you much experience or success with mixing Metronidazole and food?
<A great deal. For freshwater this is by far the better application mode>
 I feel given it's an internal problem, that may be the way to go.  Of course,
will yield to greater experience.
Thank you again
<Glad to share. BobF>

Treatment options for fungus in Jellybean Tetra (wild caught)    7/22/12
Hello again, crew!
You may remember me writing in a short time ago seeing advice on how to care for wild-caught Jellybean Tetra (Ladigesia roloffi).
I've had them (they're lovely) since Friday the 13th (O.o), and thus far things have been going well - I thought - unfortunately, this morning I noticed a cottony growth by the gill of one of them. I didn't want to stress them further, but felt it was important to show you what I see, so I'm attaching 3 images of the same fish, in the hopes that it will help you help me!
(link to photo:
This is the only obviously affected tetra at this time, though one of the others *may* have it on his top fin (which appears to have been damaged or nipped)
These two are among the smallest in a shoal of 20 - only about 1/2 inch long, if that.
Here is more info on the tank:
This is a 20g long QT tank that I set up just for them. There are more floaters now than there was when this image was taken (the day before they arrived). Most of the plants are real, except for the 'bamboo' floating - I didn't have enough floaters to provide adequate coverage, so I added some plastic ones in the hopes of easing any stress on the fish. Everything in this tank except the wood and plastic was taken from my original QT/plant grow-out tank, which was only a 10g. I didn't want to risk any fluctuation in the parameters, so moved everything over, including the substrate, plants, and filter. Also put in a 20g filter that has been on another tank for quite some time to ensure as stable of an environment for them, considering the new set up.
Ph 7.4 (a little bit high for Jellybeans)
<Yes; I'd keep under 7.0; do you have some water of lower pH to blend in? Peat or its extract to add?>

KH 2gtts
GH 6gtts
Nh4 - 0
No2 - 0
No3 - 5
Po43 - 0
Temp: 78-79 (also on the high side)
I've been trying to keep the temp low - I've read that 77 is their optimum temperature, with 79 being the max. I can't keep the tank under 78-79ish - it's just where my room temperature gets the water. I've been testing the water daily, and have seen no fluctuation in parameters since adding these fish. They are under a 10g hood lamp, which I've slowly been increasing in duration to reach 8 hours, with the intent of slowly switching to the standard size hood lamp for this tank.
<Leave this off by day, on at night... to discount it as a heat source>
The idea is to slowly get them used to conditions in my 29g community, which is where I hope they'll go eventually.
I've been doing a small water change and siphon the sand every 2-3 days.
I'm afraid to let them go a week because of the waste created by feeding them, as they won't touch food if it lands on the substrate,
<Floating small pellets, and/or flake... a few times daily>
and it's been a learning period for all of us. I've been feeding them lightly every day (I think - it's hard to tell because they're so small and so MANY of them - I'm new at this!), and have been skipping every 3rd day.
At first, they stayed on the opposite side of the tank as I siphoned (very gently and slowly, so as not to disturb them), but now they seem to have gotten used to it, and confuse it with the syringe that I feed them with and TRY to get to the siphon - so I kind of don't think I'm stressing them out with water changes, though I could be wrong.
<Better this than pollution>
I've actually never dealt with any type of fungus (if that's even what this is) in my tank(s) before, and am especially leery as they're very small and wild-caught. I sincerely appreciate any information and insight you can offer me in order to get my tank healthy again, and my little Jellybeans safely through this!
Let me know if there is any other information that might help. . . thank you very much!
<Your water quality reads as otherwise excellent. I would not treat the system for this one fish, nor remove it to treat elsewhere. I too think this may be an opportunistic infection (bacterial but possibly fungal) w/ the one fish being physically traumatized; and will heal of its own accord w/ just good care, time going by. Bob Fenner>

Disappearing tumor?    4/24/12
Hello, I apologize in advance for the lack of photographic evidence. Four months ago I bought 6 X-ray tetras to start my 20 gallon tank. The tank was fishless-cycled with ammonia 0, nitrite 0, nitrate 10, temp. 77F. Three weeks ago one of the tetras developed an inclusion in its back---a pale sphere, about 1.5 mm in diameter, above the spine and below the dorsal fin but attached to neither. There was no external sore or swelling (if the fish weren't transparent, I wouldn't have been able to see the thing.) The fish behaved and ate normally and showed good coloration. Now, three weeks later, the "tumor" has shrunk and looks like a grain of sand suspended in its back. The fish still seems healthy and none of the others show any sign of this thing. Is this a parasite? Have you seen or heard of this before?
Thank you for any insight you can give! -Julie
<Does read like a Microsporidean, Microsporozoan (colony) by colour, size, shape... as far as I know there are no specific "treatments" for such. Just good care, appropriate foods, water quality... Bob Fenner>

sick x-ray tetra, env. 12/6/11
today one of my 5 x-ray tetra is not swimming normal. kind of jerking around. like it can't use its tail. All other fish are fine. I do water changes once a week. .25 nitrates
<Do you mean nitrite... NO2?>

(I don't know why it doesn't come down...my tank has been cycled for 3 months)
<Usually insufficient biofiltration, circulation... See WWM re>
0 nitrites and 40 nitrates.
<Oh... maybe you mean/t Ammonia... toxic, as is your too-high Nitrate. Do read here:
scroll down to the yellow tray>
I just did a water change yesterday so I don't know why nitrates are that high?
<Read where you've been referred>
I don't see anything wrong with the fish like I don't see any disease or anything. could have just been sickly to begin with? but I have had them for 2 months with no issues. so what do I do? is it inevitable it will die? do I just let it die in the tank?
thanks! -Lauren
<Doubtful, read/act, and no and no. IF your water quality wasn't off as indicated by your measures of nitrogenous metabolites, I might suggest the one specimen had physically injured itself, had some sort of genetic anomaly. But you've got to address the lack of complete cycling here and cut the NO3 by at least half. Read on! Bob Fenner>
Re: sick x-ray tetra 12/6/11

Yes I did mean .25 ammonia. I have an Aqueon 30 quiet flow for my 20 gal tank. But I haven't changed the filter cartridge in a while....maybe that's why my levels are high. Thanks!
-Lauren Jerry
<I'd add another filter... and read where you were previously referred.
Your fishes are in imminent danger of poisoning by their own wastes. BobF>

Tetra issue. Moenkhausia injured, living solo 11/14/11
Well I'm not entirely sure what to do about this fish. Early September, I was placed in charge of a 55 gallon tank here at my school, first thing I did was get the water levels how they should be.
<Good start>
There were small amounts of ammonia and nitrite (less than .5 ppm, but I was not happy with that)
<Me neither>

and the KH was non existent while the GH was way over 30 (I stopped counting is was so bad). This tank is stocked with tetras, patties, barbs,
<Mmm, what species are these Barbs?>
mollies and Pleco. Everything seemed just fine, I started putting AquaSafe in the tank (slowly to ensure the fish acclimated correctly, they had been adding straight tap water for over a year and the Ammonia and Nitrite levels here are insane).
<In the source water? This is bad... would not use for my potable purposes w/o running through a reverse osmosis device first>
Everything was fine, we lost one fish (had been purchased from Wal-Mart and it looked slightly discolored when I started). Well, about a week ago now, I noticed that there was this huge blackish/brown spot on the right side of the Lamp Eye Tetra. It was swollen, so I pulled the fish and it has been in quarantine ever since. I watched it the first couple days and smaller spots began to appear on other areas of the fish, so I started adding Rid-Ich
<Mmm, I wouldn't do this. The active ingredients are too harsh... Formalin and Malachite Green>
(which has worked on everything I've ever come across without issues) and the smaller spots went away, but the swelling on that one spot has continued. I've never had anything require treatment for more than four days, so I stopped treating yesterday.
This spot now has some slight red around the edges of it now.
The fish is eating and swimming fine, but I'm not sure what else to do.
<Nothing... other than providing good care... water quality and nutrition wise... Likely this Tetra has been bruised... perhaps from an altercation w/ another fish here, maybe just a "bump" into something hard. Will heal on its own in time>
Nothing has changed in the tank in a month and a half and I even added a female Molly and a Dwarf Gourami to the tank (quarantined and added after the tetra had been removed, so they did not cause this). This fish is about 2 inches nose to tail and they are expecting me to magically cure this fish, but I'm unsure what to do for it right now. At this point, I don't think it's Black Spot. The only time I seen something even close to this before was on a female guppy who developed an internal tumor, was black and swollen, she died within a month.
Current tank stats:
Ammonia: 0, Nitrite: 0, Nitrate: 5, KH: 2, GH: 29, pH: 7.0, Temp: 72-74 degrees (depends on if the lights are on).
<Mmm, given the mix of species, this water is fine>
Thank you!
Confused Student.
<And a note re this fish, Moenkhausia spp. are strongly schooling species.
Really will do much better kept in a small group. I'd add a few more. Bob Fenner>

Spiraling tetra 11/9/11
Good morning. I have a 15 gallon planted tank with three green tiger barbs,
<Tiger Barbs are notoriously nippy in small groups.>
two rosy's,
<Rosy Barbs are subtropical fish; they also get much too big for this tank.>
and two diamond tetras.
<A delicate species unless you have soft water.>

I initially had three rosy's, but one became stuck between a rock and the tank wall and died. I can only guess he had grown too large because he frequently swam through the rock formations in the tank. Because of this, I thought it best to rearrange the tank.
<Or get a bigger tank>
I put the fish in a large plastic washbasin with an airstone and the heater while I tended to the tank. Parameters before and after have been consistent. Ammonia 0, nitrates 10-20, nitrites 0, GH 75, KH ~100, pH 7.6 .
<Sounds pretty good water for tetras and barbs.>
Anyhow, after returning home and settling down, one diamond started to list a tad. He seemed to swim ok, but whenever he swims fast, he spirals. After some Google -itis on my part, I worried he may have whirling disease and put him into quarantine that night.
<Whirling Disease is virtually impossible in aquaria, unless you're feeding live Tubifex worms. Do understand that just because your fish is "whirling" doesn't mean he has Whirling Disease; it's a thousand times more likely his nervous system is being shut down because of environmental stress, poisoning, shock, or something else like that.>
He did fine in quarantine.... I treated him with extra stress coat and wee bit of Melafix. He did well and stopped spiraling.
<Perhaps, but doubt either medication did much in this scenario. Fish that are shocked, for example, can go doolally for a few hours, but eventually settle down.>
So back home he goes and he promptly starts to spiral again. However, he schools with the other diamond (and sometimes the barbs shoal with them it's funny to see them plop down into formation. ) He eats well, he doesn't appear ill, he just lists a wee bit and spirals. He doesn't spiral during "normal" swimming, just when he "power" swims.
Now I'm wondering if he has a swim bladder dysfunction.
<Again, another common misunderstanding. True infections of the swim bladder are extremely rare, and virtually all diagnoses of "Swim Bladder Disease" are wrong. When fish are sick or weakened, they can't swim properly. Fish with swim bladders will find it difficult to balance. Think of the last time you were giddy -- I bet it wasn't because your legs were partially paralyzed! Far more likely you had a fever, you were drunk, you'd had a bump to the head, or some other thing like that. It's important to separate the symptom from the problem.>
Since stress apparently makes it worse, I'm reluctant to move him anymore. Should I try to treat him again? If so, with what?
<If the fish doesn't show signs of bacterial infection or parasitism (i.e., white spots or similar), and you can rule out a genetic problem because the fish was swimming normally when purchased, then think about the environment. What might be stressing it? Temperature? Oxygenation? Water chemistry stability? Water chemistry after water changes? Social interactions? Poisons such as copper and Chloramine? Check through these, and act accordingly.>
I'm of a mind to just let him be, keep up water changes per usual (20-50% every 1-2 wks), and see how he does. I don't think he was comfortable in quarantine as a solitary fish.
Any advice?
Thank you!!
<Cheers, Neale.>

parasitic worm infecting cardinal tetras? (RMF, other ideas?)<<Sporozoans, Microsporideans?>> 2/19/11
Dear Crew,
Hoping you can help me - I've scoured the site and can't find anything that accurately describes the situation we currently have. Last night I noticed that one of my cardinal tetras had a fluid filed sac protruding from just underneath the gills on one side,
<Do occasionally happen, for no obvious reason I'm aware of, though the usual culprits such as physical damage, stress, and parasites of various sorts can be considered.>
the fish doesn't seem to be in any discomfort and we observed it feeding ok, however on closer inspection of the other cardinals we've noticed that three of them appear to be affected by some form of worm - the fish are each showing one large 'blister' of around 3mm on their sides which appear to have a thin white worm inside, no more than 1mm in diameter. We tried unsuccessfully to remove the affected individuals from the tank last night, when examining the fish this morning one of the blisters appears to have ruptured as it now resembles a wound rather than a blister, and I noticed one of the worms attached to another tetra, but without the surrounding blister.
<Indeed. My guess would be that the blister rather than the "worm" will be the healthcare issue, because most worm-like infections can't actually complete their life cycle under aquarium conditions. They need intermediate hosts like birds or snails for that to happen.>
The tank is a 500l (134 US gallons, or 110 UK gallons) tropical freshwater system, heavily planted and is maintained at 25-26 Celsius (77-78.8 F). Ammonia, nitrite and nitrate are all undetectable, and we do 15% water changes weekly (including gravel siphoning). The current stock are:
shoal of mixed tetras (15 cardinal,
<Angelfish food.>
5 lemon, 5 Pristellas, 3 Congo)
10 juvenile angelfish (1.5 inch body length)
6 Corydoras catfish
6 Bristlenose catfish
So far the only fish that seem affected are the cardinals but I suspect if it is a parasite without a specific host then it will spread to the other fish in the tank.
Currently, the plan is to increase the number of water changes to reduce parasite load in the tank
<Water changes are a good idea for other reasons, but won't really dilute the concentration of parasites in any meaningful way.>
however am not sure whether we should also treat the tank with an anti-parasitic medication as well, and if so what would be best? We've not been able to get a photo of the affected fish but hoping you might be able to offer some advice without one
Here's hoping,
<Would recommend nothing more than acting as per physical damage for now: observe the fish, and if they show signs of their wounds not healing, medicate with something like the excellent eSHa 2000 Finrot/Fungus medication. Without a positive ID on the parasite, medicating further would likely be pointless and could well stress the fish still further. Cheers, Neale.>

Red Phantom Tetra can't open his mouth 12/18/10
Hi Crew,
I hope you can shed some light on this problem. Here's my set-up:
20 gallon tank
Ammonia 0, Nitrites 0, Nitrates 10
8 red phantom tetras, 1 Farlowella, 1 dwarf Gourami, 6 peppered Cory cats
live plants
temp 76
I've had this tetra in question for 2+ years. A bit of background that may or may not be relevant - he was either born with a curved spine, or he was injured on the trip to the LFS. From day one you could see his spine was curved. However, he has been fine for 2+ years, could swim just fine though perhaps he is tipped upward a little bit when he is stationary but otherwise has been normal.
<I see>
I noticed a few days ago he seemed to be moving a lot more, constantly swimming but not as he normally would. He is tipped upright more than usual and never rests even for a second. He also seems to be a bit stiff in part of his body but I can't quite put my finger on where (possibly his upper body but hard to tell).
When I fed the fish he seemed to react and swim around the food, but made no attempt to eat. I knew something else was off about him and couldn't put my finger on it until tonight...he isn't opening his mouth at all! Not to eat, or as fish normally open and close their mouths. It is like his mouth is fused shut.
<Mmm, happens...>
I put a magnifying glass up to him and don't see any growth or obstruction but he is so quick to move it is hard to tell.
Should I put him in a separate tank (and possibly treat with something?).
Any idea what this is, and are my other tetras at risk?
<I'd leave this fish where it is. Not "catching"... either developmental or a trauma (bump into something hard)... Will cure of its own or this fish will perish in time from a lack of nutrition>
Thanks so much for your time!
<Welcome. Bob Fenner>

White patches spreading on fish 6/21/10
I am having a problem with my rummy nose tetras getting whitish patches.
<I can see.>
This tank is cycled, 10 gal,
<Much too small for this species; Rummynose tetras are fairly demanding fish, and suffer in small tanks -- anything less than 30 gallons, to be honest -- and cannot abide immature aquarium conditions.>

I check the ammonia every week and after 3 weeks I had .50 so it has had a recent water change.
<If the aquarium has had non-zero ammonia levels for three weeks, that's very likely the cause of the problem here. Is the tank actually a mature one? In other words, one more than 3 months old? Or is it a new aquarium?>
The pale patch on the fish was noticed soon after I bought the school of four tetras about 4 weeks ago,
<Again, these tetras aren't forgiving of mistakes. Keeping fewer than 6 tetras is always a bad idea, and with Rummynose tetras your scope for mistakes is minimal. Social stress could easily make worse any other problems.>
I did some treatment with Maroxy and Melafix assuming it was fungus and it did nothing-didn't grow didn't shrink- so I quit treatment after a week and decided it just had odd coloring.
<Is not odd colouring; this is some type of bacterial infection, Finrot-type thing. Needs to be treated with a suitable antibiotic PLUS appropriate "fixes" to these tetras' environment.>
Now the whitish patch is growing and one other tetra is showing a small spot of it on its head. The fish still all have nice red faces- they get pale if they are stressed or sickly or so I am told.
<They can do, but pale heads aren't the only signs of sickness, anymore than sneezes are the only signs that humans aren't well.>
I have researched on line the only thing that seems to match is Columnaris but the fish is still active and not acting sick. My experience with Columnaris is that it is fast and deadly-had two new betas die overnight from it in March and never bought fish from Petco again- so I don't think it is Columnaris;
<Could be Columnaris, but you can't really be sure without microscope work.
Certainly bacterial, so either way, treat with something that treats Finrot and Columnaris.>
what do you think it is?
<Stress-induced opportunistic bacterial infection. You've kept these fish badly, and now they're dying. Fixing the environment -- better water quality, larger tank, more specimens -- will save them, alongside appropriate medication.>
Thanks for any help.
<No problem.>
<Cheers, Neale.>

Bariatric Neon Tetra 5/4/10
Thanks for the great site I have found it very helpful for both marine and freshwater tanks
<Good to know.>
I have searched your FAQs and other pages but cannot find an exact match for the problem.
We have a neon tetra that is significantly larger than normal i.e. at least twice the size of the tankmates While I have managed to find numerous references to bloated or swollen stomachs the associated pictures and
descriptions speak to very distended stomachs and bulging - this fish is large all over.
<Are you sure he's a Neon? Cardinal tetras are similar but a bit bigger all around. Conversely, Paracheirodon simulans, the so-called Green Neon, is somewhat more slender than the Common Neon Tetra, Paracheirodon innesi.
Also is he longer than the others, or just fatter? If the abdomen is substantially bulkier, but the length of the fish is the same as the others, that can imply a variety of things, including dropsy, intestinal worms, even a female filled with eggs and ready to spawn!>
My question is does dropsy sometimes produce this overall swelling?
<Just the abdomen. By definition, oedema/dropsy is retention of fluid within the body cavity. The head, back, tail should all be the same as usual, since the muscles aren't much affected.>
Could it be some sort of water exchange/retention issue? What would you recommend as a treatment?
<For now, nothing. If the fish is happy and healthy, I wouldn't worry too much.>
There is no signs of eyes popping or pine cone/fluffy scales
The fish has slowly increased in size over 4-5 weeks. Diet is a mixture of flake and blood worms. We have tried a pea with no success (in case of constipation)
The fish has now stopped eating - or eats very intermittently
<Again, the key thing is whether the fish is bigger around the belly, or longer and the larger more generally, from head to tail. If the belly alone is swollen, and this fish is the same length as the other Neons, then you may well be dealing with constipation, dropsy, Neon Tetra Disease or something.>
Water parameters are good -nitrate less than 10. Ph is 6.9 and although a small tank it has good filtration, weekly 30% water changes with a mix of RO/dechlorinated water (to maintain hardness) and the substrate is vacuumed weekly. The remaining 6 tetras (the only other fish) are doing fine
<Hope this helps. Cheers, Neale.>

Bariatric Neon Tetra 5/4/10
Thanks for the great site I have found it very helpful for both marine and freshwater tanks
<Good to know.>
I have searched your FAQs and other pages but cannot find an exact match for the problem.
We have a neon tetra that is significantly larger than normal i.e. at least twice the size of the tankmates While I have managed to find numerous references to bloated or swollen stomachs the associated pictures and
descriptions speak to very distended stomachs and bulging - this fish is large all over.
<Are you sure he's a Neon? Cardinal tetras are similar but a bit bigger all around. Conversely, Paracheirodon simulans, the so-called Green Neon, is somewhat more slender than the Common Neon Tetra, Paracheirodon innesi.
Also is he longer than the others, or just fatter? If the abdomen is substantially bulkier, but the length of the fish is the same as the others, that can imply a variety of things, including dropsy, intestinal worms, even a female filled with eggs and ready to spawn!>
My question is does dropsy sometimes produce this overall swelling?
<Just the abdomen. By definition, oedema/dropsy is retention of fluid within the body cavity. The head, back, tail should all be the same as usual, since the muscles aren't much affected.>
Could it be some sort of water exchange/retention issue? What would you recommend as a treatment?
<For now, nothing. If the fish is happy and healthy, I wouldn't worry too much.>
There is no signs of eyes popping or pine cone/fluffy scales
The fish has slowly increased in size over 4-5 weeks. Diet is a mixture of flake and blood worms. We have tried a pea with no success (in case of constipation)
The fish has now stopped eating - or eats very intermittently
<Again, the key thing is whether the fish is bigger around the belly, or longer and the larger more generally, from head to tail. If the belly alone is swollen, and this fish is the same length as the other Neons, then you may well be dealing with constipation, dropsy, Neon Tetra Disease or something.>
Water parameters are good -nitrate less than 10. Ph is 6.9 and although a small tank it has good filtration, weekly 30% water changes with a mix of RO/dechlorinated water (to maintain hardness) and the substrate is vacuumed weekly. The remaining 6 tetras (the only other fish) are doing fine
<Hope this helps. Cheers, Neale.>

Re Rosy Tetra Following - Please Help (RMF, any better guesses?)<<Mmm, no>> 11/28/09
Hi again,
<Hello Chris,>
Please see photo of my rosy tetra, attached. As a follow up to my last email (below), I'd been having concerns about my Rosy Tetras. Since then I've been watching and have seen no bullying, the three have been hanging out together and eating well, though still their colouring was lighter than usual.
<Usually a bad sign with these fish. Like a lot of South American tetras, Rosy Tetras have colours that can change with mood and health.>
Last night all 3 seemed okay, all ate and were swimming fine. This morning one was dead, with a thick white band on its body. I looked at my other two and am upset to find that a second looks like he is in bad shape. He has a white band as well (see photo). It is also protruding but that is hard to tell in the photo. He is swimming but didn't eat today.
<Likely sick.>
I am also starting to see what looks like the start of a white patch on my third though not as advanced. He is eating and swimming fine. My other fish are showing no signs of this thankfully.
<May be specific to the Rosy Tetras, e.g., a virus or protozoan parasite.
A parallel could be made with Pleistophora hyphessobryconis, what we call Neon Tetra Disease although it can affect related small characins as well.>
I have a 4 gallon quarantine...should I move both fish to it using cycled water and filter medium, and if so, is there anything you can suggest I do to help them (temperature, medication?).
<If this is something analogous to Pleistophora hyphessobryconis, there's no real cure beyond removing (and euthanising) sick fish to prevent cross-infection. Typically Pleistophora hyphessobryconis works its way through all the Neons (or whatever) in the system, and then dies out without harming unrelated fish (catfish, livebearers, etc.).>
Any idea what this is? And should I move both of the tetras (concerned about bullying in such close quarters by the healthier one).
<I'd destroy any sick fish that aren't feeding; they're unlikely to get better.
I do weekly water changes, Nitrite and Ammonia are 0 and Nitrates are between 8 and 10. As below, it is a 20 gallon tank.
Thanks so much! Chris
P.S. One thing I noticed is that my tank temperature has gone from the usual 78 to 75, though I would have thought this might help since they like cooler water. I am trying to regulate the temperature now, as this fluctuation has never happened before.
<Can't see relatively small temperature changes like this causing problems.
Sorry can't offer anything more helpful. Cheers, Neale.>

Follow up - It's wide-spread now - Please Help 12/2/09
Hi Neale/Crew:
Well, things have gone from bad to worse. Since writing the email below on Saturday, I've lost all 3 of my Rosy Tetras but it doesn't stop there.
<Oh dear. This really does sound like some type of highly contagious pathogen akin to Pleistophora hyphessobryconis.>
When I came home yesterday one of my red phantom tetras seemed to have pop eye in his right eye, just starting. I watched every fish closely last night and everyone ate and was full of energy, even him.
When I came home tonight I went to check on the red phantom with pop eye and found another red phantom had died (had no pop eye, no visible symptoms). He had appeared 100% normal last night. I was then shocked to
also find a dead swordtail - again, 100% normal and pushing his way around to get food last night as usual - very active and nothing unusual on his body.
<Oh dear.>
Now two of the four remaining tetras appears to have pop eye. The other two seem okay. I have two remaining black skirt tetras that appear okay.
<Oddly, Pleistophora hyphessobryconis doesn't affect all tetras, even while it *can* infect distantly related fish such as Angels and Goldfish. So you can get some very odd situations were Cardinal tetras don't get Pleistophora hyphessobryconis, but Neons do. It may well be that your Black Widows are resistant, unlike the Rosy tetras. I'm not 100% sure that you're dealing with Pleistophora hyphessobryconis -- though the loss of colours, swelling, and then death are consistent -- but there may be some other, highly contagious Sporozoan at work here.>
Six Cory catfish appear fine, one (Elegans) is appearing sluggish tonight.
My Farlowella and 5 little Oto cats seem okay.
<I would be surprised if your catfish succumb to the same thing, but as stated above, distantly related species have been infected with Pleistophora hyphessobryconis even though it's normally considered a disease of Neons. That said, I've found Corydoras elegans to be one of the more delicate species in its genus.>
I did my weekly water change last night because I was concerned about the pop eye, tested water levels an hour later and they are still great.
Ammonia 0, Nitrite 0, Nitrates around 8. That is constant for my tank.
Water temperature did not change, and I used chlorine remover in the water as always.
It hit me that a while ago I introduced 2 elegans Corys to my tank. One was lethargic from the get-go, the other was very active but died two days later. I had assumed at the time they died from the stress of travel. I think what I've learned is a very painful lesson in not quarantining, unless there is something else in my water that I should test for. I also introduced a plant about two weeks ago but not sure if that can cause problems?
<Right... this may well be the issue. My experience of Corydoras elegans was not dissimilar, having "rescued" two lonely looking specimens sitting in a tank at my local garden centre. A few days after buying them, they were both dead. I do wonder if this species is a host for some type of microbe that, under certain circumstances, can cause problems. I will add though that even though they shared a tank with some Peppered Corydoras, those Corydoras remained perfectly healthy; indeed, I still have them and every year they present me with another batch of baby catfish. So whatever it is that Corydoras elegans may or may not carry, it doesn't necessarily affect other catfish. As you say, quarantining is always important.>
Please help...I know that I will likely loose more fish by tomorrow if not sooner. Should I medicate the tank, and if so with what? I am very concerned that medication will hurt or kill my catfish (Corys and Farlowella).
<So far as I know, Sporozoans are very difficult to cure. Your best bet is to remove any infected fish on sight, and humanely destroy them. Done ruthlessly, this can sometimes stop the cycle of reinfection.>
Thanks as always for any help you can provide - I am at a loss.
<These sorts of infections are rare but always frustrating. I can't begin to tell you how many Neons I've lost (or seen others lose) because of Pleistophora hyphessobryconis. For all my (supposed) skills at fishkeeping, Neons are the one species I've never been able to maintain. In other words, usually what happens is you let the infection burn itself out, removing any infected fish and adopting a wait-and-see approach towards the others.
Typically, the fish that survive are resistant, so no medicating is required. It's debatable whether the pathogen can remain dormant in a tank with no suitable hosts, and if it can, for how long. But I'd tend to err on the side of caution and not add any more specimens of any species that succumbed in the past.>
<Cheers, Neale.>
Re: Follow up - It's wide-spread now - Please Help 12/2/09

Sorry, a bit more info if this will help.
<Fire away.>
I checked PH just now and it is right where it has always been (in the "ideal" range).
<Which is? For most community fish, around 7 to 7.5 is the ideal. Below pH 7.5, biological filtration works less effectively, and below pH 6.0 it doesn't work at all. So I tend to recommend people keep the pH just above
7, even in situations where acid-loving species are being kept *unless* acidic pH levels are critical to their health (as with Ram cichlids for example).>
I don't know what else to test - everything is fine. I think my Elegans is okay, as he is active now. I might have caught him during a rest.
My two red phantoms definitely have pop eye but are active. I have noticed the one who had pop eye last night seems to have it a bit worse today.
<Would isolate these in another tank, and realistically, euthanise them.>
I've just examined every single fish and there is not a single symptom I can see. No loss of colour, fins are not clamped or torn, no white spots, no fungus. Nothing is visible other than the two with pop eye. All are active and eating.
<For Pleistophora, and perhaps other Sporozoans, the main transmission mode is when healthy fish peck at weak/dead fish, so it's important to isolate sick fish from the healthy ones.>
That is also how it was last night which is why I'm shocked that my sword and tetra, who appeared in perfect condition and were active and feeding were dead today.
I should also mention that none of my fish was dead for very long, in fact most of them that had died in a breeding trap.
<Would not use a trap. When isolating these fish, you absolutely should isolate them: another tank, and with nothing moving between this tank and the display tank. Euthanasia is often more practical.>
If one looked bad in the evening I would place him in the trap so the others couldn't consume the body in the event he died overnight. I had hoped this precaution would prevent any further contamination.
<It won't; circulation of water through the trap into the tank will allow pathogens to spread.>
Finally, my tank is well established and I have had no real problems with water quality or fish loss in the 2+ years it has been running.
I hope this additional can help you help me! Thanks again for your thoughts.
<Cheers, Neale.>
Re: Follow up - It's wide-spread now - Please Help 12/2/09

Hi Neale,
Thanks very much for the prompt response.
<Not a problem.>
As expected, when I checked the tank first thing this morning I could barely tell apart the 4 remaining red phantoms from the 2 black skirted because all have lost all colour. They are essentially transparent now. I have moved them to another tank.
<Sad news.>
I've noticed that the tail of my remaining sword has a tiny little bit of raggedness on the tip (barely visible) which wasn't visible last night so I'm watching him closely.
<Do so; while I'd be surprised if he caught the same pathogen as the tetras, it's not impossible. The symptom you describe sounds more like physical damage, or possibly Finrot, though this latter isn't common in well run tanks.>
Otherwise he was happily devouring a catfish pellet this morning and was active.
Thankfully all Corys, the Farlowella and the Oto cats seem great, in fact they seem to be enjoying the new-found space.
<Also good news.>
The only positive in this is that the fish seem to be succumbing very quickly - it doesn't appear to be a slow decline so hopefully they aren't suffering too much.
<This is actually a typical characteristic of Sporozoan infections: by the time symptoms are visible, the fish is days away from death.>
One question - should I be doing 10% water changes more frequently than once/week to try to remove the pathogens, or keep to the weekly schedule?
<You aren't going to "dilute" the pathogens, so for the sake of simplicity, I'd stick with the usual 25% water changes per week.>
Thanks again, Neale!
<Sorry I can't offer anything more helpful. Cheers, Neale.>
Re: Follow up - It's wide-spread now - Please Help
Thanks again, Neale.
Even though the news isn't great, your support is very helpful. I'll focus now on hoping the remaining fish survive.
<Good luck with it! Cheers, Neale.>
Re: Follow up - It's wide-spread now - Please Help 12/3/09

Hi Neale/Crew:
I am probably taking a shot in the dark here but I'll ask anyway, regarding my ongoing saga of fish dying (see below and recent emails with Neale).
My six remaining tetras are still translucent with no colour whatsoever but they are eating and otherwise seem okay. They are in a separate tank. I don't hold out much hope but I see no signs of distress at the moment.
But I just witnessed something in my 20 gallon tank (which was the source of the significant fish loss recently - see past email thread). I have 5 Oto cats in that tank that have been there for roughly 4 weeks...not too long after I introduced them did I discovered the rosy tetras starting to decline.
I have never seen them bother with the other fish...however just now I put an algae wafer on the bottom and the Corys scurried over to eat. I saw two of the Otos also go to the wafer. Then one of the Otos tried to suction on to one of the Corys and was successful for a moment! He then tried to do the same with my sword who swam away. This is the first time I've ever seen one of the Otos interact with the other fish. The other fish seemed scared and went to hide.
<Unfortunately, this is very common behaviour. I have seen it myself, and I've mentioned it repeatedly here at WWM. The problem is that Otocinclus view the mucous on the flanks of fish as potential food. Whether they do this only when starving, or do it regardless, is not clear to me. But slow moving fish are targets, and this is one reason I keep telling people to shy away from Otocinclus, despite the sales pitch that they're "ideal small algae eaters". They are nothing of the sort!>
Wondering if this behaviour was just competition over the algae tablet...or is it possibly that my fish have been dying because of this?
<It can cause physical damage, and that should be obvious. I my case, the poor Awaous flavus goby had its flanks torn up, and a bacterial infection set in similar to Finrot.>
I know that there can be confusion between certain algae eaters, some being more aggressive than others, but I didn't expect that from Otos and hope they weren't the cause of my fish loss!
<I wouldn't expect Otocinclus to parasitise tetras.>
Again, a shot in the dark, I know, but thought I would ask.
Thanks again!
<Cheers, Neale.>

Help with Rosy Tetras, sys.... env. hlth. 11/20/09
Hi Crew,
<Hello Chris,>
Hoping you can give me advice on my Rosy Tetras.
<Will try.>
Tank set-up:
20 gallon planted tank
<20 US gallons? A bit on the small side of this species... will hide a lot.>
Ammonia 0, Nitrites 0, Nitrates 8 -10
15-20% water change every week (diligent about water quality and testing)
Temp 78
Community tank with Corys/Otos/2 swords/3 Rosy Tetras and 6 Serpae tetras, and a Farlowella
<Serpae tetras are aggressive nippers, and not my first choice for the community tank (English understatement... wouldn't let them anywhere near community fish).>
I've had my 3 Rosies for 1-1/2 years and realize now that I should be keeping them in larger groups, but I think I would be overstocking if I added 3 more fish.
<Indeed... but my prime concerns are that some of these species, the Rosy tetras and the Swordtails, really do need more swimming space.>
Lately one has been hiding, and this fish, along with one of the other Rosies, are losing colour and appear to have some blotchy darkness/redness internally. It seems in the gill area as well as toward the middle of the fish. It is very subtle as is the colour loss (at first I thought I was overanalyzing), and I wonder if I'm seeing the start of some sort of infection due to the stress of bullying, as one of these Rosies has started harassing the other two...no nipping, just swimming quickly at them until they hide. All 3 are eating normally, and all fins look good.
<Likely a symptom of general stress, though whether it's the size of the tank, or nipping from the Serpae tetras, I can't say. To be honest, if there were six of them in a 20 gallon tank without the Serpae tetras, I think they'd be okay, but the Serpae tetras really aren't good choices for keeping alongside Rosy tetras.>
If this is what the problem is:
(1) If I remove the "bully" (and hope that the other 2 recover) would he survive in a 10 gallon tank with 4 Corys and a dwarf Gourami? Would the Gourami be bullied too? Or would it be better to move the Gourami to the big tank and put the bully Rosy in the small tank with the Corys which he doesn't seem to bother with (so far).
<Not a good idea. Keeping these fish in a 10 gallon tank really would be pushing your luck. Removing bullies rarely works in situations like this, where the problem is the group is too small for normal schooling behaviour.>
(2) If I remove the two Rosies in question and quarantine them, I would have to put them in a small 5 gallon tank (heated and filtered). Would this small tank stress then further?
Should I medicate the water?
<Not unless you detect symptoms of a particular disease.>
Thanks in advance for your advice!
<You're welcome.>
<Cheers, Neale.>
Re: Help with Rosy Tetras 11/20/09

Hi Neale,
Thanks for the quick response to my question re my Rosy Tetras that look like they are losing colour and have some darkish/red internal problems.
<See, this is the thing... all these tetras can change their colours significantly depending on mood. Their colours can range from pale salmon pink through to almost a fiery red. Further, the idea of "internal
problems" is common parlance for "haven't a clue what's wrong". It's actually pretty uncommon for fish to genuinely have some mysterious bacterial or viral infection. (Some exceptions though, like Dwarf Gouramis
and their viral and Mycobacteria infections.) Anyway, while it's not impossible that your fish have some bizarre bacterial infection, I'd tend to bet against it. Evaluate all the other possibilities. Unless there are
obvious symptoms of a bacterial infection -- such as loss of appetite --
I'd tend to assume this problem was more behavioural than anything else.>
I did some more homework and the fish I identified as Serpae tetras are actually red phantom tetras - sorry!
<Ah, now things become interesting. Red Phantom Tetras, Hyphessobrycon sweglesi, formerly Megalamphodus sweglesi, are not a tropical fish. They need fairly cool conditions, 20-22 C being ideal. When kept too warm they never do well, and tend to be short lived. So instead of 5+ years, you get a couple of years out of them. So while ideal for other low-end tropicals like Danios, Neons and Peppered Corydoras, you wouldn't keep them with, for example, Dwarf Gouramis or Angelfish, both of which need above 25 C to be happy. It's a very common mistake to assume tropical fish all like really warm water; many of them don't.>
The receipt I had filed away only said "tetras" and I thought Serpaes looked like them but it is in fact red phantoms. I've had them for two years and they are extremely peaceful little guys.
<Yes, they are a nice species.>
Re the swords and the rosy tetras, I agree that a 20 gallon is too small and if I were to do it over again I would make other choices.
If you think I should add 3 more Rosies to try and help the 2 that are being bullied I will but worry that I am going to be overstocked. What do you think?
<Worth a shot.>
In my 20 gallon I have:
6 very small Oto cats
<These like cool water too.>
1 Farlowella
<As do these.>
6 Corys (3 are very small - I forget the name - and 3 are peppered so are a little larger)
<And these too.>
2 swords (fairly large swords)
<Also should be kept below 25 C.>
3 rosy tetras
<These do need middling temperatures, around 24-26 C.>
6 red phantoms (very small)
<As we've seen, like things a little on the cool side.>
Would adding 3 more rosy tetras to this mix make it a dangerous load?
<Assuming robust filtration, I don't think you'd be running too much of a risk.>
As I mentioned I do weekly water changes and it is has been years since I have had a water quality issue but am concerned.
I am concerned that the internal discolouration/redness and colour loss of the two tetras will get worse if things remain status quo.
<I would be worried too.>
Thanks again!
<Good luck, Neale.>

Neotrop community tank; sickness, death, but no useful data - 10/24/09
I have 55 gal freshwater tank with Black, Red, and Gold Tetras 1 Pleco and 2 Cory cats.
<Hmm... not really sure what these "tetras" of yours might be.>
The Tank has been going for about a year and I haven't lost a fish in about 10 months until about 1 month ago. I lost 2 black Tetras in a few days with no on obvious signs. One of my reds lost color and was having labored breathing and died about 2 weeks later. Now one of my Golds is showing signs of labored breathing and has raised scales on his sides all others seem to be doing fine. NO2, NO3, KH, GH are all within normal ranges
<What are "normal ranges"? The thing is, without knowing the actual values, I can't say anything sensible. But let's recap. For most South American tetras and catfish, you're aiming for these values: Zero ammonia, zero nitrite, carbonate hardness around 5-10 degrees KH, and a general hardness around 5-15 degrees dH. The pH should be around 6.5 to 7.5.>
I do about a 20% water change every two weeks and use AquaSafe and Neutral Regulator by Seachem at changes
<Please, check the water chemistry/quality values are as stated above.
Usually, when random species start dying for no obvious reason, and the symptoms are nebulous things like dropsy and heavy breathing (as is the case here) then environmental issues are to blame.>
What do you think is Killing my fish.
<Cheers, Neale.>
Re: Neotrop community tank; sickness, death, but no useful data- 10/25/09

Thanks for your time and your response. I'm sorry I can't give you a better name on the tetras but I only know them as Black, Gold and Red long fin Tetras. The water chemistry is NO3 = 20ppm, NO2 = 0ppm, PH = 7.0, KH = 40ppm, GH =60ppm, Ammonia = 0ppm.
<Sounds mostly okay. The water hardness is low, and while not in itself a problem, do understand that in soft water the pH is prone to dropping, so I tend to recommend people maintain freshwater communities at slightly alkaline conditions, around 4-6 degrees KH (about 70-110 mg/l CaCO3).>
These values are reached using API test strips. There have been no new fish added to the tank for at least six months. There are two filter systems on the Tank. I know that without seeing the tank or fish that a diagnosis difficult. I have rechecked the water values and they are as stated I don't know the conversion for the KH and GH from ppm to deg.
<Easy: 1 degree KH is 17.9 mg/l.>
however as I stated the API kit I use says these values are within the normal range for tetras.
<Indeed, but what fish experience in the wild isn't necessarily what's easiest to maintain in captivity. Do read here:
I know that Tetras aren't the most exotic of fresh water fish but I enjoy them and hate to loose any. The only fish that seems to be exhibiting any symptoms at this time is a Gold Tetra about 3"long, the symptoms are
labored breathing raised scales and I noticed 1 red spot about 1mm on one side just below his dorsal fin and a lack of appetite, all the other fish seem to be behaving normally and appear normal. I hope that I have given you enough information to give me a suggested course of action to save my fish. Thanks again for your help.
<Difficult to say what the problem is here. Heavy breathing tends to imply changes in environmental conditions, typically to the worse. So for example non-zero levels of nitrite and ammonia, or sudden changes in pH, or poisoning of the tank with insect spray, paint fumes, or whatever. Raised scales are associated with Dropsy, and that's a symptom of organ failure, typically the "end game" of a systemic bacterial infection or similar. Red spots on the body are inflammations or open wounds. These can be caused by all kinds of things, from physical damage through to certain viral and bacterial infections. So there's nothing here that yells out the name of any one problem. My instinct here would be to do a big water change to flush out any potential toxins (say, 50% today, and another 50% tomorrow) taking care that water chemistry of the new water was close to the water chemistry of the old water. I'd give my filter a clean, just to make sure it's working properly. I wouldn't feed the fish. I'd check the heater was at the right temperature. I'd look over the tank for signs of serious decomposition: dead fish, uneaten food, dense clumps of algae, dead snails, etc. I wouldn't treat the fish until I had a clear idea of what the problem
might be; most medications are toxic to some degree, and a "scattergun" approach rarely works out the way you'd like. Cheers, Neale.>

Please help! Tetra hlth. 9/10/09
I looked on your page to find out some info on my little fish. He is a red eye tetra and for the past 3 days he has had something resembling the shimmies and cannot swim. He lays on his side or back at the bottom of the tank breathing very slowly and when he tries to swim or move he looks like he is having a seizure. He is getting very small because he can't eat and I'm not sure what I can do for him. He doesn't have any discoloration and the other two fish in the tank are normal. We have a few other neon tetras and I changed out 20% of the water yesterday and the temperature is correct for the fish tank. Please let me know if there's anything I can do.
<Hello Caroline. With very small fish, symptoms such as these are not promising. The first thing is to check the aquarium conditions. Do a nitrite test and a pH test, just to make sure everything is okay. Yes, it's
only one fish sick *now*, but if he's the smallest or weakest, he might simply be the first of many. Next, see if you isolate the fish. A quarantine tank is ideal, but otherwise, a floating breeding trap is useful. Put the fish in there, and observe closely. Sometimes, fish go "loopy" if exposed to a short-term shock; I've done this to my fish one time adding freezing cold water (obviously, without thinking what I was doing!). As they warmed up, they settled right down again. So, if there's something amiss, perhaps water quality, a sudden pH change, or the use of a pesticide spray in your house, water changes will help, and you may see the
fish improve. All this said, with very small fish there's usually little to be done. Do have a read of the best euthanasia methods, so that you're prepared to relieve suffering if it doesn't look like he'll get better.
By the way, Red-eye Tetras (Moenkhausia sanctaefilomenae) are somewhat hierarchical and can be nippy; keep in groups of 6 or more specimens to prevent bullying. Some tetras will turn on one another if kept in too small a group. Cheers, Neale.>

Black Phantom Tetra - Help Needed 8/22/09
Hoping someone can shed some light on a problem I'm having with one of my Black Phantom Tetras. I'm afraid I'm losing him.
Here's my set-up:
20 gallon aquarium, live plants
1 Farlowella
3 swords
7 Corys
3 black phantom tetras
6 red phantom tetras
<Does prefer fairly cool conditions... not really a very good community fish above 23 degrees C.>
I just tested my water levels:
Ammonia - 0
Nitrites - 0
Nitrates - 8
Temperature 78 degrees
I noticed a few days ago he was hiding underneath a plant and wouldn't come out when I was feeding them. He seems to be resting at first glance, but his black markings are fading and his top fin is a little more limp than the other fish. I haven't seen him eat in a few days. He seems to be able to swim fine if he is swimming along the bottom, though I've only seen him swim a few inches at a time, and not frequently.
About an hour ago I was watching him. He had emerged out from hiding and was at the bottom, in the middle of the tank. He suddenly took off like a shot upwards - I thought he was going after some food. But instead of swimming in a straight line, his body was rolling and tumbling at top speed as he swam upwards. It happened so fast that I couldn't really tell quite what his body was doing. He is now back at his resting spot under the plant.
<Variety of possibilities, but bullying is the one I'd think about...
should be in groups of 6+, and in smaller groups, bullying will lead to stress, and stress can cause the symptoms you're seeing.>
When he is resting his body appears normal, no "u' shape, bloating, or moving in circles or going upside down.
<Stress, starvation, secondary infections all possibilities.>
Any idea what could be wrong? I was concerned about whirling but I've never fed live food, and his back half is not darker, in fact it is lighter since he's lost much of his black markings. I see no lesions or anything else odd about him.
All other fish appear fine.
I do have a 10 gallon quarantine tank though it is not set up...should I transfer some water from the larger tank so it will be cycled, and then transfer him into that tank? Is there anything I can do to help him?
<Maybe add a bunch more, and see what happens.>
Thanks so much for your time.
<Cheers, Neale.>
Black Phantom Tetra -Additional Info 8/20/09

Hi again,
I've been reading up on Whirling, and I saw that it can be caused by eating a dead fish (?). Just wanted to mention that I lost a fish last week, and suspect that it had been dead a couple of days before I found it (I usually do a daily head count but didn't for a couple of days). It looked like the fins had been nibbled.
This was one of my red phantom tetras. Approx. 8 months ago it developed a tiny black dot inside it's body and over the last many months this growth has slowly spread. Right up until the end he was schooling and eating and energetic, but I guess the growth/disease took its toll. He did not show any symptoms that the black phantom is showing.
Just thought I would mention that, in case it was relevant.
Also, in doing further reading, I came across Neon Tetra Disease, and False Neon Tetra Disease. Does the black phantom's condition sound like either of these, and if so, can you explain the difference?
<Not likely Pleistophora... but quite likely a Sporozoan/Microsporidean manifestation... common in wild-collected Characoids of S. America... as small, discrete, black shiny dots, raised against sides... Not usually fatal, unless other stressors are at play>
I also read that one of the first symptoms is whitish patches, which I don't see in my fish.
Thanks again!
<Welcome. Bob Fenner>
Re: Black Phantom Tetra -Additional Info 8/22/09

Thanks, Bob.
<Welcome Chris>
This morning I saw a new symptom...periodically the fish is in a vertical position, with nose to the gravel and tail skyward. He is not doing well at all.
Could you please expand on your note below - if it is Sporozoan/Microsporidean as you suggest it could be below, what do I do? I assume he should be quarantined. Is there any medication that can help?
Note that I haven't seen any black shiny dots on him at all, he is very pale and his formerly black markings are now very light grey.
<There are no known medications for such...>
Is Sporozoan/Microsporidean the same as Neon Tetra disease?
<"All newts are salamanders... not vice versa"... NTD is in the same organismal class...>
Should I be concerned for my other tetras?
<Only if they ingest the present afflicted one (i.e. if it dies)>
If you could provide more info, or direct me to a link, that would be most helpful.
Thank you so much for your time.

Congo Tetra with red spot on his head. 4/17/09
Howdy, y'all rock!
<Modest forbids...>
I have a problem, well I have a bunch of them but that is a different story :)
My Congo Tetra has a red spot on his head, right at the top of the gill.
Pictures are worth a thousand words so check out the attached pictures. You can find the full size images at.
You really need to look at the full size images, the images I attached don't have all the detail you need. I figured you didn't want me sending multi-megabyte pictures.
Oh boy, this history on this fish is too long. He has survived cotton mouth and various other ailments in his 4 year life. Some of our other fish were not so lucky with the cotton mouth. We found some red spots on our Congo Tetras shortly after the cotton mouth cleared up. It killed our other Congo Tetra. It spent over 2 weeks in a 10g quarantine tank before it got better.
We tried Maracyn, parasite killer and some food laced with antibiotics (I can't remember the names of the treatments). That was about 3 months ago.
Since then the tank has been stable and no problems.
Yesterday we found the spot. Any ideas?
<Very difficult to say; most likely physical damage and/or secondary infection. An antibacterial treatment should help, but double check water quality and relationships with other fish. Congo Tetras are quite nervous animals, and apart from being nipped, they can jump into the glass or hood when alarmed. Anyway, assuming the water quality is good (0 ammonia/nitrite) and water chemistry within the range for the species (pH 6-7.5, 5-15 degrees dH) I'd treat as you would Finrot, and hope for the best.>
I am hesitant to move him to the quarantine tank, he just darts around and beats himself up on the glass and we don't want to get a bigger QT tank right now.
<Don't quarantine a single Tetra; as you say, he's not going to like it.>
He is exhibiting no odd behaviors, his eating and activity are normal. The other fish don't have any signs of damage. We have just used some Melafix in the tank, our Yellow Spiny Eel dug himself into a hole and lost some skin, used the Melafix as preventative measure.
<Melafix pretty unreliable.>
The eel was 100% better after only a few days.
<Unfortunately these small Spiny Eels (Macrognathus spp.) do get damaged by gravel, and in my opinion, should only be kept in tanks with a soft, sand substrate.>
What the heck do we have, and don't tell me a tank full of fish:) And what do we do about it.
<Some type of antibiotic or antibacterial; Maracyn is as good as any place to start, but anything that combats Finrot should work.>
Levels are good. Nitrate 0, Nitrite 0, Ammonia 0, Phosphate trace.
CO2 is controlled at 7
Temp is a 79 degrees
Lots of plants
Lots of fish.
2 Eheim 2213 filters
1 UV Sterilizer.
Lots of lights.
2 cubes of blood worms every night.
There are no leftovers.
Thanks for any, and all help.
<Hope this helps, Neale.>

Extremely thin tetra - is she diseased? 9/5/08 Dear WetWebMedia Associate- <Ave,> I owe a nice 35 gallon freshwater tank with not that many fish (only 12, among them 8 tetras, 3 albino Corys, and 1 Pleco) but with plenty of aquatic plants. In general, I do not have any problems in / with the tank, the water is fine, the fish are healthy. I am a big fan of Bob Fenner's "natural" treatment of water so the weekly changes of 1/3 of my tank's water are a commonplace. <Sounds good.> I noticed that one of my tetra fish is 1/3 of the size of other tetras. Indeed, from the beginning it was smaller than the rest of the group. But, the way I see it now - it is way too thin. It's fins are huge, its eyes and head looks unnaturally big. This resembles me the pictures of a starving human-being. <Ah, yes, does happen. It may be genetic, a developmental problem, or physical damage such as damage to the jaws. Could conceivably be a parasite; live Tubifex worms especially can cause problems in this way. What kind of tetra are we talking about here? My gut feeling is that this is simply a "runt" and there's not very much you can do about it.> I was observing that fish eating habits and noticed that it tries to eat but whatever it takes to its mouth, it "puffs" back. Seeing this now, I am afraid that my fish is dying from starvation :--(( I offer my fish a variety of foods - krill, shrimp, Tubifex worms, blood warms, and all kinds of flakes. But everything is dried - no "life" or frozen food. <Good.> I mix the food before supplying. Also, I feed them once a day, in the morning. The rest of the fish look big :--) not to say "fat." This little tetra is the only one that wants to eat but it cannot :--( <Could be damaged in some way, or with a blockage caused by a tumour or cyst. With very small fish there's not a lot you can do. Force-feeding such animals tends to cause more damage.> I noticed that this tetra when it gets a piece of food, holds to it firmly and swims around with it. But, it does not eat it. Other fish bite everything and try to get as much as they can. <Does sound like physical damage. You could try offering some Liquifry (that's food sold for feeding baby fish). This is softer and easier to slurp. Alternatively finely powdered flake food or hard boiled egg yolk (sparingly!) can be offered. See if it is able to eat these foods.> Do you know what is going on with my fish? I look over its body - there are no signs of parasites or any outside diseases. The only scary think is its extremely thin look. Is there anything I can do for my fish? How can I help it? <Not sure you can.> Please, let me know. Thank you very much for your help. Anna <Sorry to say, but I suspect the outlook for this fish is grim. If the fish is big enough to manhandle, then a plastic pipette to squirt in some minced prawn or flake food suspension can work. But for that the fish needs to be above a certain size, something about the size of an adult Platy. Anything smaller would be too easily damaged. Putting the fish in a floating breeding trap might offer some respite from competition, and you could see if finely powdered or liquid food was accepted. But my gut feeling is that nothing will help, and this fish will, eventually, die. I suppose you could treat with an anti-helminth medication (e.g. Prazi Pro) but the problem seems to be eating food, not digesting it, so I don't think gut parasites are the issue. Sorry can't offer better news, Neale.> Re: Extremely thin tetra - is she disease? (RMF, thoughts?)<<Mmm, nope. RMF>> 9/5/08 Thank you very much for letting me know, Neale. I will try the liquid food solution; hopefully my fish will get better. Anna <Fingers crossed! Do hope this works out, and good luck! Neale.>

Neon Tetra with Ich and Pop/Cloudy eyes 8/30/08
I have a neon tetra with 1-2 spots of Ich and pop and cloudy eyes.
<Treat promptly for Whitespot and Finrot/Fungus. Here in England I'd be using eSHa 2000 and eSHa EXIT, medications for these complaints that are safe to use together. In your country the range of options may be different.>
I can also see white extended patches on his body.
<Well, if this is Neon Tetra Disease (Pleistophora) there isn't much you can do, but a combination Finrot/Fungus medication like eSHa 2000 would be if something less else.>
The fish is pretty strong, eats normally, swims normally and does not rub against rocks or plants. I isolated the fish in a hospital tank, but I'm wondering how I should treat it. I bought Melafix and a remedy for Ich,
<Melafix... largely useless.>
but I'm not sure which one I should use first. I'm also planning to buy food with antibiotics so that I can treat the intestines too. What do you suggest?
Thank you,
<Not a big fan of randomly treating for internal parasites unless there's evidence the fish is genuinely sick from them, and that's very difficult to judge. Antibiotics obviously have ZERO effect on the internal parasites that aren't bacteria, such as Pleistophora (a protozoan) and Camallanus (a helminth) so again, you need to know what you're dealing with rather than randomly pulling stuff from the shelves and hoping for the best. Cheers, Neale.>

Glowlight tetras with constipation? 8/9/08 Dear crew, <Evan> I was looking at my aquarium tonight when I noticed 3 of my Glowlight Tetras (Hemigrammus erythrozonus) were displaying the same symptom. All three had some sort of stringy clear/white excretion hanging from their anuses. I'm thinking it could be constipation but worried it could be internal infection/parasites. <or just...> I have never had this problem with my Tetras before. There are 7 in a 10G tank (parameters NH3=0, N02=0, NO3<5, pH=8.0, <Mmm, this is too high... I'd "fix" in the change-out water ahead of use> GH ~ 6, KH ~ 6, I change 30% water every 5-7 days). <Great> I feed TetraMin tropical flakes, freeze-dried bloodworms, occasionally sushi Nori. 6 days ago I added 5 Red Cherry Shrimp to the tank. 2 days ago I added some blanched cabbage to the tank for the shrimp to munch on. Last night I put some pantyhose (stockings) material around the intake of my power filter so any baby shrimp wouldn't get sucked into the filter. Could chemicals from the pantyhose cause this sort of reaction? <Mmm, not likely> Could the cabbage have done something to their bowels? <Yes> All of the fish have good color and energy, they have been eating well and otherwise show no symptoms of disease. Should I take any action or just wait and see? <Definitely the latter... Very easy in such a small volume, with the shrimp present, to induce troubles> I have included a couple pictures that tries to show the problem, they are a little blurry. <These are excellent images!> Thank you for your help. Evan <Bob Fenner, would just be patient here>

Tetras (Neons & cardinals) dying one by one in the dark in a planted aq. 8/7/08 I hope you can help. Please forgive the length, but I wanted to give you all the info I could think of. <OK.> 30g L, been up for about 8 weeks (cycled with seed filter from friends established tank), custom hood with AHsupply 96w CF bulb (3.2W/gal), eco-complete substrate mixed with fine gravel. Fluval 205 filter. Stealth 100W heater. <All sounds good.> Tank has the following plants (most of which are thriving): Cabomba (2 bunches of 5 stems each), Moneywort (4 bunches of 3 stems each), Melon Sword, Chain sword (just a baby), Microsword (2sq in patch), Ruffle plant, Wisteria (just finally establishing its fine submerged leaves - 1 bunch of 3-4 stems), Broad Ludwigia (1 bunch of 3-4 stems), small Java fern, small Anubias nana, and a large bunch (about 15-20 long stems) of Anacharis (from a friends established tank). Sounds crowded, but you'd be surprised how open it really still is. <At least some get pretty big -- Echinodorus osiris for example will quickly take over a 30 gallon tank if it thrives; mature plants can be 50 cm tall and 30 cm across! Echinodorus martii likewise.> To this there's the following fish: 5 spotted Corys, 6 Otos, 3 "mystery" snails, 6 zebra Danios, and originally 8 each Neons and cardinal tetras. <Right, well one issue here will be temperature. To wit, Neons prefer cool water, 20-24 degrees C; Cardinals need warm water, 25-28 C. There's no "happy medium" at which both can be expected to do perfectly well. Corydoras, Otocinclus and Danios are also cool-tropical fish, and will thrive at 20-24 C (I'd go for 22 C). But that's too low for the Cardinals. So one way or another, at least some fish are going to be heat or cold stressed.> The light is on a timer to cycle 6 hours on in the morning, followed by a 3 hour off break mid afternoon, then another 6 hrs on in the evening. Then off for the remaining 9hrs overnight. <OK.> All was well, the plants are thriving, the fish too. <Good.> Then I added the Anacharis about 2 weeks ago. Suddenly I'm missing cardinals and Neons overnight, just 1 or 2. at a time. Never noticed any trouble with the actions/attitudes of the tank mates, everyone pretty much sticks to their schools. But the losses continued. Everyone looked fine when the lights are on... healthy, active, feeding. It was great. Well it's a great mystery alright. <Well, Neons and to a lesser extent Cardinals can be plagued with "Neon Tetra Disease" and will drop off one by one until the cycle of infection is broken. But it is also possible the new plants brought in a predator, such as a Dragonfly nymph.> I finally started watching closer at night and I found that after the lights been off for about 90 minutes (+/- 15 minutes) I notice a gradual and frightening change. Both the cardinals and Neons lose nearly all coloration going nearly white/clear. <Quite normal.> Then one or two of them start going bonkers and lose their equilibrium swimming upside down, backwards and on their sides, barrel-rolls, tumbling end-over-end, etc., then death. <That is odd.> Turn the lights back on and gradually (within 20-40 minutes) all coloration has returned and activity resumes normally. <Ah, now, this is curious. Have you checked how pH is affected by photosynthesis? When plants photosynthesise they remove CO2 from the water, allowing the pH to rise. When they stop, CO2 accumulates and pH goes down. Alternatively, some (but only the minority) can perform "biogenic decalcification", and I believe Anacharis is one of them. What this means is that they remove carbonate and bicarbonate from the water as the source of carbon for photosynthesis instead of CO2. This is why these plants prefer hard water. Anyway, in the process the water loses its carbonate hardness and consequently its pH buffering capacity. The net result will be that pH will drop while these plants are photosynthesising, and the water pH will also become less stable with regard to other pH altering processes.> My water parameters have been rock solid since the beginning: Nitrite 0; Ammonia 0; Nitrate "nearly" 0; kH 5deg; GH 12deg; pH 7.6; chlor. 0. I've even tested right before and after a light cycle and saw no appreciable difference. Temp stays between 78.5 and 80.5F. <Do check the pH and carbonate hardness through the day to test my hypotheses above.> My thought were CO2 poisoning - but the zero change to pH leads me to believe the CO2 isn't reaching toxic levels. Second thought - The plants are using up all the available O2 (I'm not aerating) at night thereby starving the smaller, more sensitive tetras. So I added a small airstone to the corner of the tank and set a small air pump to kick on when the lights go out (my timer has day/night outlets). It didn't seem to help. <Leave CO2 off for a few days and see what happens. Won't harm the plants.> Last Saturday night was the worst, within 2-1/2 hours three tetras gone (down to 6 now, 2 cardinals & 4 Neons left), and all the fish (except the 5 Corys, 2 largest Danios, and 3 largest Otos) were pale. Even with nighttime aeration. <Hmm...> So as a stopgap measure I retooled the timer to cycle the light and dark to 3 hrs light, 2 hrs dark ('round the clock). Two nights of success now with no casualties... but even though there is the requisite "amount" of light and dark I cannot imagine the rapid time cycles are any good for either the fish or plants long-term. <It isn't good for the plants; they need a certain length of time simply too start photosynthesising, and 3 hours won't be enough.> My next attempt will be to get a larger air pump and drive an 18" bubble wand across the back of the tank rather than the small airstone driven by the smaller air pump. I know this will drive out more CO2 to the detriment of the plants (though probably not too much), but it should eliminate the worry of CO2 poisoning, and should add O2 in the dark for the plants and fish to (hopefully) share. Also, I'll be raising the filter spout up closer to the surface to provide a little more surface agitation (currently its about 2in below with no agitation). <Not sure this is the issue.> Finally, since this all started after adding the fastest grower in the largest number/mass plant-wise (the Anacharis). It's possible that plant addition might've pushed the balance over the edge with respect to CO2 and O2 respiration. So I'll be pulling that out and trimming it back to a more manageable (2-3 bunches of 4-5 "short" stems each) size. <Hmm...> Hopefully then I can gradually return to slowly extending the light/dark cycles to a more natural rhythm and keep my fish healthy and my plants growing. Any thoughts? other suggestions? etc? Anything I missed? Mark <Cheers, Neale.>

Ick/Whitespot 7/22/08 Hi Guys, I added five new baby neon tetra's to my tank recently - it seems the neon's have all developed Ick/Whitespot. I already had 6 Neon's 2 guppies and a Sailfin Molly - these all appear to be fine. <So far at least... http://www.wetwebmedia.com/FWSubWebIndex/mollies.htm Do review the needs of Mollies, and also be warned Neons may nip the fins of fancy male Guppies.> I have read your articles regarding ICK and just wanted to confirm your recommendation for best way to treat. <Promptly!> I was just going to buy meds and treat the tank with meds and regular water changes. However from reading through your site would you recommend increasing temperature and treating with Salt instead? <Makes no odds either way. I tend to use commercial medications such as eSHa EXIT (a brand I find works well even with sensitive species like puffers) because it's easier. But if you want to use salt/temperature, go ahead.> I have added salt before but never with the neon's only with mollies/guppies can my neon's tolerate salt? also my temp is at 80f already is it safe to increase the temp further? <Neons should tolerate the very low salt concentration required, particularly if you build up the salinity across a few days. As for raising the temperature, I wouldn't. Temperature is about speeding up the life cycle of the parasite; in itself it isn't a "treatment" as such. The idea is that the salt only kills the free living parasite, so the sooner that phase begins, the better.> Thanks in advance Scott <Cheers, Neale.>

How to keep bacteria alive in a fishless tank? Pristella maxillaris; health (Bob, second opinion?) Mmm, nope. RMF 7/19/08 Hello Neale, <Hello Giuseppe,> hope all is well for you. One of my Pristella maxillaris is in distress showing a dark area in the intestines at the bladder level. I always noticed a small dark area in the same place in that fish, but now the dark area is bigger and the fish tends to hide in a cave during the day, swimming in circles almost horizontally. The Pristella doesn't eat almost anything at this point. When I turn the lights off it gets out of the cave and swims with the other fish. Is there any medicine you would recommend? <This isn't something I recognise, I'm afraid. X-ray Tetras are usually very robust but they are (I believe) wild caught, so it is possible this one has an intestinal parasite of some kind, and that's what you're seeing in these famously transparent little fish. Because internal parasites usually have very complex life cycles, the risk to your other fish is very small. (Normally the small fish is eaten by a predator, like a bird, and then the parasite leaves the bird to infest more fish somewhere else via the bird's droppings.) If the fish is showing no signs of getting better and all the signs of simply getting worse every day, I'd make a judgment on its quality of life. If it was having a bad life away from the school and generally not doing fun tetra things, I'd painlessly destroy it. Small fish are difficult to treat when infected with anything other than light cases of external parasites/infections.> Thanks, Giuseppe <Cheers, Neale.>

Cardinal with blister/worm? -05/07/08 Hello WWM Crew! First, I have to thank you for the invaluable resource that you provide to all aquarists. Your website is brilliant: a veritable mine of information! That being said, I (of course) have a problem. <Thanks for the kind words.> One of my cardinal tetras has me stumped. At first, I thought he/she had mechanical damage from running into something in their habitat. Later, a sizable white spot developed inside of a large, clear blister. Additionally, on this individual only, a large swatch of black has developed beneath the eyes bilaterally, stretching from the mouth towards his/her gills. The black "stripe" lies beneath the iridescent blue scales that cover the cardinals body. For the time being (and since the "blister" started to develop some time ago) the cardinal is acting entirely normal, schooling with the 29 others, eating extremely well, full cardinal colour, no scratching or abnormal behaviour. A second cardinal has begun to show the lighter/clear patch of discolouration that preceded the "blister." <Ah, given the "syndrome" is spreading, I'm obviously thinking about Pleistophora as a possible cause. Whilst Cardinals do not seem quite as susceptible as Neons, they can still catch the so-called "Neon Tetra Disease". There's no known cure, beyond breaking the cycle of infection, which seems to be sick/dead fish releasing infective stages that get into healthy fish. Isolating symptomatic fish is the preferred first step.> Tank specs: ammonia, nitrite, 0. Nitrate, less than 5, more than 0. Soft water, pH 6.8, mixed treated tap and RO. Fluorite substrate, heavily planted. Tankmates: 30 cardinals (two symptomatic), four M. altispinosus (asymptomatic), one SAE (asymptomatic). The tank has been fully cycled for about 6 months (fishlessly, so much easier! Why doesn't everyone do it this way?). The tank is kept at 82 degrees F. Partial water changes are done at least weekly (often times more often there is still sediment on all of the plants from the Fluorite!) and the gravel is vacuumed each time (around the plants). <All sounds ideal for tetras.> I found a reference on WWM to worms growing in blisters on a Raphael Cat. Is this one and the same? <Blisters can of course be caused by a variety of things. People get blisters from things as diverse as badly fitting shoes and Bubonic plague. So one should be very careful about assigning causes to just one symptom of this type. What's more specific to Pleistophora is changes in colouration, loss of appetite, shyness, and then eventually death. Infected fish, particularly species other than Neons, can last for many weeks even months before death.> I found the reference here: http://www.wetwebmedia.com/FWSubWebindex/catfshdisfaqs.htm . However, the same individual got two different answers from two different experts (you guys really are): "This is likely some sort of "worm" parasite (more likely a digenean trematode/fluke but maybe a nematode) The Paragon might help... there are other vermicides... Levamisole, Fenbendazole, Piperazine... that might be tried" and "The blisters are really bacterial infections eating away the flesh of the fish. Treat with Nitrofuranace after you do a 30% water change and serviced the filter." <Blisters can indeed be caused by both these things. Unless you're a microbiologist, it is really impossible to know what the problem is. So the best you can do is run through the likely causes one at a time, trying different treatments.> There was also a reference to Dieter Untergasser's "Handbook of Fish Diseases": "There is one treatment method suggested in there that sounds like it should work (method C6)." I am afraid that I do not have this book, as I have never had any trouble with disease in any of my tanks (well, I rehomed African Cichlids for someone else that had been horribly abused, but that required nothing more than better husbandry and a larger tank). I checked local libraries with no success. I will purchase it now, but I'm afraid it will be a couple weeks to arrive. May I enquire as to this "method C6"? <No idea I'm afraid. In any case, with very small fish, the fish often doesn't last long enough for the treatment to work. It's simply a size issue. So while I'd certainly consider isolating and treating infected fish as best as I could, in this case if it *does* seem to be "catchy", I'd perhaps painlessly destroy both fish to stop the problem spreading.> If this is what is mal-affecting my cardinal(s), how should I treat? Should I treat everyone in situ or should I remove the affected individuals to the hospital tank? Do I need to tear down the tank to stop everyone getting infected if this is a parasite? Would they best be treated orally or as a bath? If I have to treat in situ, is there a medication that is plant safe, or do I have to remove the plants? I have attached a photograph of the cardinal (and learned that cardinals are camera shy, and move fast!) that shows the blister, white spot, and black under his/her eyes. I just noticed that the photo makes the cardinal look like it has Popeye, but I can assure you that it is only a trick of the light. <Isolate the infected fish for sure; perhaps maintain them for 2-3 weeks simply by providing good food and water and see what happens. Treat with an antibiotic or antibacterial if you want. It is possible the blister is nothing worse than a secondary infection caused by (for example) fighting. In this case, you should see some signs of improvement. But if the fish continue to deteriorate, get back in touch. At worst, you've isolated the potential source of infection and your other tetras should be fine. I have long since given up keeping Neons because of the plethora of mystery diseases they seem to come supplied with. Cardinals, though more expensive, are tougher and better value in my experience. But even so, you might be unlucky.> Sorry for the novel of an email, but I wanted to provide you with all of the information I could. Thank you for all of your help, and the excellent resource you have compiled for all of us (it is becoming harder and harder to resist that reef tank). <So they tell me.> To you and yours, a wonderful day and weekend. Thanks, <Cheers, Neale.>
Re: FW Cardinal with blister/worm? 05/08/08 Hello Neale, Thank you for your advice on my cardinal issue. I have isolated him/her in a separate tank, and am working on catching the second. I hadn't even thought of NTD! Urg! The possibility didn't even cross my mind, since the fish is just as active as the rest of the school, and still the first to food. <Which all sounds positive, so fingers crossed the blisters heal by themselves.> There is also no white necrotic tissue present- only a clear blister (still with regular, bright colouration beneath, despite how the picture appears), with an Ich like spot inside. <Odd.> But...alarm bells ringing! When I took the cardinal out of the tank, I noticed that it does have a "lumpy" appearance. I hadn't noticed, because it is so subtle that you can't see it except when looking at the cardinal from above. <Well, keep an eye on things. Do provide the isolated fish with shade and good clean water so it isn't too unhappy.> As far as an anti-parasitic, do you have a recommendation that may work? <Wish there was. So far as I know, nothing works reliably, or even half the time.> I figure that if it is NTD, an anti-parasitic won't do any more harm. I would rather not sacrifice the fish if I do not have to, but in the event that they do begin to suffer, I will certainly break out the microscope. <I certainly hope the boffins at the "fish medication" labs come up with something for Pleistophora; it's a real plague and so depressing to watch. But breaking the cycle of infection/re-infection is essential, which is what you've done.> Thanks again, Tianna <Good luck, and keep us posted. Neale.>
Re: Cardinal with blister/worm? 5/10/08
Hello again Neale, I hope you are enjoying your weekend! <Indeed I am! A lovely summery sort of day here in England.> I think the mystery of the white-sphere-filled-blisters on the cardinals has been solved. I went to perform a water change on the hospital tank, and ARGH! What appeared to be nematodes, of all different lengths, free swimming in the tank. The white spot (which, I guess, is a mass of subcutaneous parasites) in one of the cardinals had shrunk considerably. <Never seen this, or even heard of it. Sounds quite nasty. In any case, I'd immediately use some sort of antibacterial/antibiotic to prevent secondary infections caused by the burst cyst. An anti-helminth drug such as Prazi Pro should deal with the nematodes. But that said, most worms have complex life cycles that can't be completed under aquarium conditions (for example, they need to go through a bird or snail before they can back into a fish). So provided there were no secondary infections and the Cardinal otherwise recovers, I'd actually be cautiously optimistic.> This brings up another question that I will beg your help with. <Indeed?> Since removing the two symptomatic cardinals from the display tank, the "mystery illness" had gone wild. Nearly half of the cardinals are now showing symptoms. Clearly, there are nematodes in the tank that I can neither see, nor remove. Would it be more beneficial to just treat the entire display tank, and stop torturing the poor fish in a "naked", uncycled hospital tank (especially if there are parasites living in the display that will simply reinfect the fish again)? <In an uncycled tank, you can use Zeolite to remove the ammonia directly, and that's cost effective and reliable with very small fish like Cardinals.> As my hospital tank is only 10 gal, I cannot realistically move all 30 cardinals plus the other inhabitants to tear down the display to disinfect. I could be wrong, but I think this would do more harm than good. <Agreed.> Before the "big break" in this mystery, I had purchased some of Seachem's Cupramine as a shot in the dark. Would this be effective against the subcutaneous nematodes, or would I be better served by exchanging it for something like Praziquantel (if I can find it)? <Cupramine is certainly worth a shot before trying anything else.> I always quarantine new livestock, so seeing this now, after several months in the tank and having been quarantined for a month prior to moving to this display is mind numbing. I guess nothing is fool-proof! <Quite. As I say, this disease is something I've never encountered. Possibly Bob Fenner can offer more advice.><<Sorry to say, RMF is out traveling and without sufficient internet access. -S.M.>> Thank you so very much for all of your help (both on this mystery, and the rest of this website!) <We appreciate your kind words.> Have a great weekend, Tianna <Enjoy your weekend, too. Cheers, Neale.>

Question about spot on neon's mouth 3/26/08 Hi folks, I have a 10-gallon tank with a male Betta, two neon tetras, a frog, and two algae eaters (the kind that stay little, not sure of the name). They have all lived together for several months. I clean the tank every other week, this usually keeps the nitrates under 10. <Neons need to be in groups of 6 or more; in smaller groups they are stressed and unhappy. Please note that fish couldn't care less about cute names. But what they want is that you work around their biological needs. In the case of Neons, that means company! Keeping them in too-small a group is animal cruelty, however you choose to rationalise it.> One of the Neons (Zippity) has a dark spot on his lower lip. I recently had a problem with stringy algae and thought he may have gotten some stuck on his mouth, but it hasn't come off in a couple of days. He is able to eat. Should I put him in the hospital tank in case he is sick and could pass it along to the others? <No. It may simply be physical damage, in which case it will heal. But do also be aware that things like Mouth Fungus and Finrot can start as small blisters or sores. So as ever, check your nitrite level before you do anything else.> Also, should I be adding aquarium salt to the tank? <No. Almost all fish diseases come down to water quality issues. Almost none come down to not using salt!> I don't now because I thought I read that Neons don't like salt, but did read that it's good for disease prevention. <They don't and it isn't.> Thank you! Alice <Cheers, Neale.>

Re: question about spot on neon's mouth Thank you for the advice. I will keep a close eye on the spot. The two Neons are the last two from a school - I will make sure they find a new home with other Neons as soon as he recovers. <Very good. Good luck, Neale.>

Black Skirt Tetra Infection? Help! 2/29/08 Hi, I have a 75 gallon well-established planted aquarium. The water parameters are good and all the fish have been healthy for about 5 years now. Today I noticed that a black-skirt tetra is ill. It is swimming abnormally - it's tail keeps falling and it makes brief jolts forward to right himself. It looks stressed and on closer inspection, it's torso area behind the operculum is red and swollen. I will try to catch him and put him in a quarantine tank tomorrow (not so easy in a planted aquarium) but what is wrong with him? An infection? What is the best way to treat him? Are the other fish in danger? Any help is appreciated. Thanks in advance. Kim <Hello Kim. Difficult to say precisely what's happening here, but it is certainly possible it has a bacterial infection of some sort. I'd try something like Maracyn and see how things go. Do remember to remove carbon from the filter, if you're using it. There are some parasitic infections that cause the gills to inflame, most notably Velvet, so do check for that (typically an off-white powder on the body). But parasites don't normally get into tanks unless you've added new fish. A photo might help pin things down. Cheers, Neale.>

Dying Tetras 2/10/08 I have been reading through your site and couldn't get a definite answer about my dying neon tetras. So I was wondering about my neon tetras. I recently added 12 neon tetras to my old school of 5. So my school of 17 looked awesome, but then I lost half of my school in a few days. <This seems to happen quite often with Neons, and is one reason I have stopped keeping them and don't recommend them. The quality of the mass produced stock is fairly poor, and I suspect depends a lot on the use of antibiotics. As soon as the fish arrive at the retailer, the antibiotics wear off and the fish become increasingly sensitive to opportunistic infections. This may be aggravated by the fact most people keep Neons far too warm; in the wild their preferred temperature range is 22-25 C, so compared with most other tropical fish, they need something a little cooler. Failing in this regard may be stressing them, leading to greater sensitivity to infections. Pleistophora ("Neon Tetra Disease") may also be prevalent. Although more expensive, Cardinal tetras strike me as being better value.> The aquarium is 55 gallons and my water parameters are fine except for pH which may be a little high (7.6). <Well within their tolerances; if acclimated, Neons have been know to do well at up to pH 8, 30 degrees dH! Water quality and temperature are probably much more significant issues.> Ammonia is 0ppm, nitrites are 0ppm, and nitrates are about 10-20ppm. My other fish in the aquarium are 1 dwarf Gourami, 2 blue gouramis, 1 gold Gourami, 4 rainbow sharks. I also have 4 crayfish in my tank, biggest on is about 3 inches long max. I am thinking maybe they are catching my Neons and eating them. <Crayfish will indeed eat small fish. Under no circumstances can crayfish be considered safe additions to the community tank. While it is true crayfish are mostly herbivores in the wild, in aquaria they can easily catch small fish. Because Neons sleep close to the bottom of the tank, crayfishes could easily catch and eat them.> I actually saw one snacking on a tetra but not sure if he caught him. It might also explain why I only actually see a few of my Neons dead while the other ones are just not there. <Do check for signs of Pleistophora: Infected Neons lose their colour, become shy, stay away from the group, and often hide under plants. A few days later they're dead. Pleistophora is highly contagious once the fish is moribund or dead because opening the body cavity (e.g., as other fish eat the corpse) allows the parasites to swim into the water. The only way to effective stop Pleistophora is to remove infected fish on sight. They should be painlessly destroyed, as there is no reliable cure, and certainly not once the disease because sufficiently entrenched that you can tell the fish actually has it.> They didn't jump out of the tank because I have a very tight fitting canopy and there's no dried up tetras on the carpet. One more thing too, if my pH is to high I was thinking about using water from a local spring in which the pH is about 6.4, and no ammonia, nitrite or nitrates. I would also run it through my deionization filter to make sure any harmful things would be removed. I would greatly appreciate your help and advise. <Mixing soft water with hard water out the tap is fine. I do this by mixing rainwater with tap water to good effect. Filtering the spring water or rainwater through carbon will remove any nasties, but generally such water sources are at least as safe for fish as tap water, perhaps more so. In any case, do always remember to make water chemistry changes slowly, perhaps doing 25% water changes each week until you reach the desired level of hardness and acidity. Now, the crayfishes will not like soft water. They need to be removed anyway, but just as a heads-up, in common with all crustaceans, "the harder the better" in terms of healthcare. Also remember that as hardness drops, so does pH stability, and many is the aquarist who's softened the water in their tank only to discover the pH suddenly drops between water changes. I'd not take the hardness below 10 degrees dH. Remember: fish don't care about pH, so long as its stable; what matters is *hardness*, as that directly influences osmoregulation. Cheers, Neale.>

Black Tetra, hlth. 12/5/07 Hello, In my mothers aquarium is a Black Tetra that has a small black growth below his lower lip, he is listless and has a very faint red hue on it's body every where except in the center. The fins are not red that I can see. He has not eaten in a week that I have seen and he has a little bit of a clear feces. I put in some furan 2 for 2 days, <... for what purpose?> did a water change and added some more for 2 days and I see no improvement. Can you help me. Thanks for any advice. thanks Sherri <Could you send along a photo? I suspect this may be a genetic issue... Many Gymnocorymbus have such difficulties nowadays... Do you have other individuals of this species? What other livestock is present? What re your water quality tests? Bob Fenner>

Tetra illness question Oct 22, 2007 Crew, <David> As I was feeding my son's fish yesterday, I noticed one of his day Glo tetras was missing from the action. I found it in the back of the tank and it looked awful. It was bloated, opaque, had white spots on its sides, its face was yellowish, and its tail fin was looking ragged. Any idea what is wrong. <Mmm, yes... Likely the protozoan called "Ich"... though could be some other... e.g. Chilodonella...> Tank specifics 10 gallon tank 4 day Glo tetras 2 swordtails 1 male guppy The tank has fully cycled and has been running for 5 months. The guppy and one tetra were recently added (2 weeks ago), <Likely the vector/s here> but had gone through a full 28 day quarantine with no signs of disease. <Oh! Good for you> Tank also has a 15watt compact fluorescent bulb and 3 plants as well as some algae eating shrimp who like spectrum fish food and freeze-dried Tubifex worms a lot more than algae. Water parameters Ammonia = 0 Nitrite = 0 Nitrate = ??? (can't find my kit....Grrrr) <Maybe a factor, but not a definitive one. That is, the infesting agent had to be borne from somewhere> Temp = 80C General Hardness = 13 pH => 7.6 (top of scale) Any ideas as to what might be happening? Thanks for you help! David <I would treat as if this were Ich... unfortunately the temperature cannot be manipulated upward... as the livebearers don't tolerate this well. Please read: http://www.wetwebmedia.com/FWSubWebIndex/fwich.htm  and the linked files above. Bob Fenner>

HELP!!!! Massive Tetra deaths, need help tonight! 10/23/07 Hey guys, <Hello,> sorry, I'm not gonna spell check this, hopefully you can get back to me tonight, and don't worry, I wont be offended if you don't post this on the FAQ's.... <Hmm... not sure it works this way.> I came home today to find 11 out of my school of 23 Glowlight tetras floating. they were all alive and fine as of 8 am this morning, and when I got home at 7 they were floating with bulging bellies (some were gutted with their entrails hanging out...) am at the north end of the san Diego fires right now (not in the path, but we might be evacuated tonight) I'm not sure, but I've heard of power outages in the area, so the tank could have been un powered for quite some time... I did a 1/3 water change yesterday, the same way I always do, with the same water treatments. I'm not sure what caused this, and I might be evacuated tonight and unable to return for a day or so. please let me know if there is anything I can do to protect the rest of the tank residents when/if I am gone I'd appreciate it! <Massive sudden deaths of fish can be caused by two different things. The first is a crash in water quality. While filtration is certainly one thing to check, the other is pH; tanks lacking carbonate hardness are intrinsically "unstable". On top of this, all tanks have a tendency to become acidic. So without a carbonate hardness "reserve" in the water to mop up those acidifying chemicals, it doesn't take much to tip a tank over the edge into a sudden pH drop. I've seen tanks go from pH 7 to below pH 6 within a couple of days. There's a bit of a positive feedback too -- acid-hating plants, like Vallisneria, will die off when the water becomes acidic, and as they die, they decay and produce more organic acids, and that speeds up the acidification process even further. This is why I consider hard water a "blessing in disguise" despite the fact it isn't ideal for many aquarium fish: for all its shortcomings, hard, alkaline water is stable and resists water chemistry changes. In the meantime, check for possible sources of acidification: dead animals, rotting plants, etc. The second thing that causes sudden fish deaths is toxins. Insecticide, paint fumes, even tobacco fumes can cause real problems. Adding non-aquarium safe objects to a tank, such as wood that's been treated with pesticide, is also dangerous.> thanks, and be safe Bob, I know you're right in the middle of this too. <Anyway, if you are worried about possibly doing without power for periods of time, then invest in some large lidded buckets. I have 5 gallon buckets for this. Into each, put small groups of fish. Partially fill with water, and replace the lids loosely so air can get in. You can then move these to a warm part of the house. Changing water in the buckets on a daily basis is essential. Why do things this way? There reasons: water changes will compensate for filtration; and secondly deaths of fish in one bucket won't place any of the other buckets at risk, so you can "micromanage" fatalities; and finally you don't have to deal with dead/dying plants, snails or whatever. You can easily replace those if you want, but should the fish be in there when they die, the decay mops up oxygen and stresses the fish. I've safely looked after fish this way for days on end. Good luck, Neale>
Re: HELP!!!! Massive Tetra deaths, need help tonight! 10/23/07
Hmmm, so it probably has something to do with the peat I added to the filter about a week and a half ago to help soften my very hard tap water. and then changing 12 gallons out of 36 with water not treated with peat? it looks like I will have to just stick with stable, hard water. is it best to just pull all of the peat out immediately or gradually? <This sounds very likely to be the cause of the problem. Sudden changes in hardness and pH, even from "bad" to "good" values, can be lethal. I don't personally like adding peat to aquaria as a softener. Peat is very unpredictable, and once the water starts to soften, the pH can drop precipitously. Much better to have the aquarium filled with chemically inert materials (silica sand, gravel, etc) and then adjust the water outside the tank, e.g., by mixing hard water with a certain amount of rainwater or Reverse Osmosis (RO) softened water. (Note: not water from a domestic water softener; while lacking in carbonate, this has high levels of chloride, and simply isn't "soft water" as aquarists mean it.) Once you have the water you want, you can add this treated water to the tank in increments, allowing the fish to slowly adjust to the new conditions over a few days. Since there's no peat actually in the tank, the pH and hardness in the tank should be basically stable. For a standard community aquarium, you only need to slightly soften hard water for good results. A pH around 7 and hardness of 10 degrees dH and 5 degrees KH is just about perfect for most community fish. There's no real benefit to softer, more acidic conditions unless you're spawning exceptionally sensitive fish such as Cardinal tetras, wild-caught Discus, Chocolate gouramis, Rasboras, etc. For simple maintenance, the above conditions are just fine. Indeed, some degree of (carbonate) hardness is desirable because it inhibits the background acidification that happens in all aquaria over time. In the meantime, if your fish are alive and feeding, assume they've adjusted, and make adjustments back up to your hard water conditions by doing no more than 20% water changes per day. Slowly but surely is the way to win the water chemistry game. Either that, or don't play at all, and stick with your baseline tap water conditions. Hope this helps, Neale.>

Tetra buoyancy 10/20/07 Dear Crew, <Hello there! Andrea with you this afternoon.> Today after feeding my Tetras I noticed that 1 of my Neons is floating toward the surface and actively swimming to stay lower in the aquarium. I feed them tropical flake food with the occasional freeze-dried bloodworms. <Sounds delicious...> I hadn't noticed this behavior before today so my theory is that he sucked in some air while eating. My water parameters are as follows: Ammonia, Nitrite and Nitrate all 0, pH 7.8. <pH is a little on the high side for Neons, but I wouldn't worry much. You might add some driftwood as a decoration to the aquarium to soften the water and bring it down. What does concern me is that the NitrAte is at 0. How long has the aquarium been up? Generally speaking, in the FW world, we want to see a little nitrate, as it lets us know that the tank isn't cycling. You should have something of a reading...5, 10, 15 ppm at least. What kind of test kits are you using? You might take a sample to the local fish store and have them test it. Having zeros across the board usually tells me that either the tank is brand spanking new, or the test kits have gone bad.> I do a 40% water change every 5 days. <Excellent regimen. Keep it up!> I don't feel that it is a water quality issue, he's not listing around or floating head up or down, but when he stops swimming he floats to the surface. <Could be swim bladder dysfunction. It's not fatal, just looks funny. Do a search on WWM for Swim Bladder for more information.> Is there anything I can do or is this just a "wait and see" type of thing? <If he is otherwise acting healthy, stool looks normal, eating well, I'd just let him be. Could be needing a good burp, could be the food is too fibrous, could be swim bladder, could be something else. You might also try giving him some mushed up blanched peas, in case he has a mild case of constipation.> If it is air and he can't expel it, is that a fatal condition? <No, the air will find a way out, one way or another ;-). They are kind of like us in that way.> Also, how long could it take for him to recover from this? <It really depends what it is. If it is swim bladder damage, he might always be that way, and it is just a quirk. If it is something else, it may pass, or it may not. Worst case scenario is he has some problem that is affecting him neurologically, such as a bacterial infection or parasite, but I'd say the chances of that are relatively slim if he is eating and otherwise well. Unless he shows other symptoms, I'd just call him "Bobby" or "Floaty" or "Bouncy" or something cute.> Thanks for your help, <Anytime!> Evan <Andrea>
Re: Tetra buoyancy 10/29/07
Andrea, et al: <Hi Evan, sorry for the delay. I have been out of town.> Thank you for your help earlier. <Most welcome.> I wanted to update you on the situation. After about 5 hours "Bob" seems to be back to normal. <Glad to hear it.> I've only been keeping fish for 3 months, so when I saw his behavior I was surprised and alarmed. <It happens to all of us. I've been keeping fish for years and years, and still panic often. The same with my cats, frogs, lizards, toads, nieces, nephews....call it human care instinct. =). It does ease up a bit though.> And on the water tests: I'm using Jungle 5-in-1 and Ammonia quick dip tests so the readings aren't super precise and some of the tests have a large gap between values. On the Nitrate the scale is 0 then 20 and it was definitely not 20. <The test strips are good for getting a general feel of water conditions, but since you are new to the hobby, I really suggest you get better test kits, with liquid reagents. They really are an invaluable tool, especially early in the hobby when you are just learning. The accuracy will help you both learn and get a better feel for the conditions in your tank. API makes good kits for freshwater that are reasonably priced and readily available. You will want to have Ammonia, NitrIte, NitrAte, pH, kH, and possibly Phosphate on hand. Salifert are also excellent, but more expensive. It will serve you and your fish well to buy these and familiarize yourself with them and their properties.> Again, thank you all for your continuing help to all of us fish keeping novices and experts. <Our pleasure.> -Evan

Mysterious repeated hatchet fish death  10/18/07 Hi, I hope you can have an answer. <We'll try.> We have a 10 gallon tank with live plants, 3 platys and 3 hatchet fish. two day after we introduced the hatchets, we found one of them dead. Went to the store bought another one, next day dead. <Hatchets aren't the easiest of fish. Which species are we talking about here? There are two common types, Marble hatchets and Silver hatchets. The Marble hatchet is Carnegiella strigata and it is small, mottled brown, and quite delicate. It needs to be in groups of 6 or more to have any chance of surviving. In ones and twos they just die. Not recommended for your tank simply because they will feel trapped and get stressed. When stressed, they jump at the glass lid or lamps, and damage themselves. The Silver hatchet is Gasteropelecus sternicula. It is larger, silver, with a blue horizontal band on the flanks. It is basically hardy once settled in, but mortality during the first few weeks can be very high. Given its adult size and high activity level, not really an option for a 10 gallon tank.> The water is fine, Ph between 7 and 7.2 temperature around 76-78. The community is fine and the plant are thriving. We are feeding them with Spectrum the small fish formula. We thought they might be jumping and hurting themselves on the hood. <Happens.> The deaths happened during the day. Thanks a lot Emanuela <Give up with Hatchets. Your tank is not really suited to hatchets. While lovely fish (I keep Silver hatchets) they are far from easy fish and best suited to expert fishkeepers or aquarists prepared to set aside a large, quiet, thickly planted tank where they can be kept in large numbers. If you want a surface dweller of some type, look at something like Sparkling gouramis (Trichopsis pumila) which are hardy, colourful, and do well in small tanks. Cheers, Neale.>

Tetras with Ich 09/17/07 Dear crew, <<Hello, Evan. Tom with you.>> I have a 10 gallon tank with 4 Glowlight tetras and 3 neon tetras (I had 5 Neons originally but 2 died soon after arriving home from the LFS). That raises a question; one of the dead Neons was completely colorless when I found it. Could the cause of death been NTD? <<Could be, Evan, but not very likely. Your other Neon Tetras would have almost certainly contracted NTD by now and I cant guarantee that the Glowlights wouldn't have been affected, as well.>> If so: how long before any of my other fish exhibit symptoms? Its been over 2 weeks and I haven't noticed the fish acting sick. <<They have shown signs by now, Evan.>> Sorry for the digression, back to my original question. <<No problem.>> My tank has 0 Ammonia, 0 Nitrites and less than 20 ppm Nitrates, temp 84F, pH 7.8. <<The pH levels are high for the Neons in particular, Evan. Not necessarily a problem but might account for some stress in these fish.>> 10 days ago I noticed the start of Ich on a couple of the Glowlights and I started a treatment of Aquarium Pharmaceuticals Super Ick Cure (Benzaldehyde Green and Povidone/Colloid mixture). I have been treating at half dose but following Doug Thamms recommendations found here: http://fins.actwin.com/articles/disease/ick2.php. I have the temperature at 84F and have performed 2 full administrations (5 mL initial dose followed by 5mL more 48 hours later, followed by WC after another 48 hours, and repeat) and I am in the middle of the 3rd administration (10th day). I have done 50% WC in between each. The treatment appeared to be working as the Glowlights had lost all of their white spots. <<Glad to hear this. Nice description of your regimen, by the way.>> Yesterday evening I noticed one of my Neons with Ich spots on its tailfin and body. Is it normal for the Ich to re-emerge during treatment? <<Not necessarily normal but certainly possible. Difficult to determine the resistance the parasites may have to the medication particularly at partial dosages.>> Should I increase the dosage strength to 100% doses? <<I wouldn't do this unless the problem looks like its getting the better of you and the fish. As I alluded to earlier, your Neons prefer water that's soft/acidic. Their preferred pH levels top out at about 7.0 which means your water is much higher in pH than they really like. This alone can contribute to diminished resistance to infestations such as Ich. Since medications also lead to stress, the least effective dosage that you can treat at will be far better in the long run.>> Should I just continue my treatment until no spots are left? <<Yes.>> Should I change medication to something like Quick Cure with Malachite Green/Formaldehyde? <<Not unless the API medication just doesn't do the job for you. The Malachite Green is highly effective but isn't without problems of its own. Highly toxic and has been described as a potential carcinogen. Not a treatment protocol to take lightly.>> Besides the Ich, the fish seem healthy, they are active and eat well. <<Very good signs, Evan.>> Thank you for your help. -Evan <<Happy to be of assistance to you. Good luck to you. Tom>>

Re: Ceramic media, air pumps... Actually Neon Tetra... dis., repro. 09/13/07 Hello Neale, <Hello Giuseppe,> as you know I have 2 adult Neons in my tank. One of them has a larger abdomen compared to the other one, so I assume I have a male and a female. <Indeed. According to Baensch, the difference is also seen in the shape of the blue line: on males it is straight, on females it is bent. But I can't see any difference!> Now, I noticed that every 6-8 weeks the female becomes even larger and tends to eat much less and spend most of the day in a quiet spot of the tank. This situation lasts for about 10-15 days, after which her abdomen goes back to normal and she starts eating normally. <Odd.> Do you think that she might have eggs during the time she's more swollen and doesn't eat much? <Sounds plausible enough. Do keep an eye out for Neon Tetra Disease though: key symptoms are shyness, loss of appetite, and loss of colour. Then they die! NTD is unfortunately very common.> If this is the case I would be very fascinated in trying to breed the two Neons. I read that it's pretty challenging, but that experience would be extremely exciting for me, considering also that neon tetra is one of my favorite fish. <I'm not sure it's "difficult" per se, since these fish are bred in their millions on fish farms. The problem for most aquarists is Neons only breed in very soft water. The other big mistake people make with Neons is to keep them too warm; while they aren't subtropical fish, 26C (79F) is the top of their preferred thermal range, and for breeding they only want around 24C (75F). When kept in hard, overly warm water they just won't spawn, or if they do, the eggs become fungused.> Do you also have any good web site where the breeding process for Neons is described in detail? <Is there nothing here at WWM? Breeding Neons follows the same basic pattern as most other tetras. Soft (<2 dH), acidic water (5-6); low light levels (i.e., no lights, lots of shade); little to no water movement; and benthic plants like Java moss to catch the eggs. Sunlight can be a good spawning trigger. Eggs hatch in one day, free swimming 3-4 days later, when they take Artemia nauplii and the like. If you're interested in fish breeding, there's an excellent book by Chris Andrews called 'Fish Breeding'. It's my bible for fish breeding. You can usually pick up used copies on Amazon and the life for a dollar or two.> Thank you, Giuseppe <Good luck, Neale>
Re: Ceramic media, air pumps... Actually Neon Tetra... dis., repro. 09/13/07
Neale, <Giuseppe,> I just bought that book. I was thinking about what you said about the water conditions needed to breed neon tetras and I have a couple of questions: 1 - Currently the tank where they live has a temperature of 78F and PH at 7.0. If I setup a second tank with lower temperature and acidic water, wouldn't the Neons have a shock when I move them from one tank to the other one? <Small water temperature changes don't harm freshwater fish; indeed, they are often important spawning triggers. If you're moving the fish from one tank to another, then doing the normal thing of placing the fish in a bucket of "old" water and dribbling in the "new" water over 30 minutes will not only adapt them to the new water chemistry but the water temperature too. If you're taking the fish across a dramatic water chemistry change, e.g., from hard water to very soft water, you would probably be wise to fill the breeding tank with hard water and then do soft water changes of around 20% each day until the water chemistry had changed over completely. Do also remember that very acidic water doesn't support biological filtration. You will need a small air-powered box filter filled with ammonia-remover for such a tank. There's a good argument for not filtering the tank while the parents are actually spawning and when the eggs are sitting in the moss. Only start the filter back up once the fry are free swimming.> 2 - If the Neons have to be kept in dark conditions but with plants in the tank, wouldn't the plants die for lack of light? <Yes, if you kept the lights off all the time. What you're aiming for is to put the Neons in the tank for a week, and once settled down, turn off the lights so the tank only gets natural light, and once they've laid their eggs and the fry are free swimming, turn the (subdued) lights back on. Regardless, the level of lighting should be low, and the peat extract in the water will make it quite murky. Java Moss will tolerate this regime fine. I have one tank that simply receives natural light from a window and the Java Moss has gone wild. Baby fish love the stuff, because it collects detritus and micro-organisms that they can eat. There's obviously a balance between having a nice rich microflora and a dirty tank though! Some people skip plants and use synthetic mops of various types, home-made (boiled dark-coloured yarn, teased into threads and then knotted) or purchased. There are really many options.> 3 - How long does it typically take from when the Neons are moved to the breeding tank to when they actually spawn? <No idea, never done it myself. Typically fish take a few days to settle into a spawning tank, but once there, if they're mature enough to breed, they will do so almost at once. The key thing is conditioning the female: lots of live foods so that she gets nice and fat.> Thank you, <Cheers, Neale>

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