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FAQs on the Neon Tetras 2

Related Articles: Neons, Cardinals & Their Kin; Selection, Maintenance & Healthcare by Neale Monks, Cardinal Tetras; A School of Beauty, Part II,  by Alesia Benedict, Characid Fishes

FAQs on: Neon Tetras 1,
FAQs on: Neon Tetras Identification, Neon Tetras Behavior, Neon Tetras Compatibility, Neon Tetras Stocking/Selection, Neon Tetras Systems, Neon Tetras Feeding, Neon Tetras Disease, Neon Tetras Reproduction/Breeding,

Related FAQs:  Cardinal Tetras, Characid/Tetra Fishes,

Help with neon tetra      6/15/17
<12 megs; groan....>
Dear Crew at Wet Web Media,
Tank - 100 liter
Ammonia 0, Nitrite 0, Nitrate 15, GH 10, KH 7, PH 7.5
8 cherry barb, 8 emperor tetra, 7 neon tetra, 2 phantom tetra
Fluval external canister filter, internal air driven sponge filter.
I have previously kept a 50 liter tank and decided to move to a 100 liter about 6 months ago. I quarantined all fish for 6 weeks and tank was cycled from the start as I used media from old tank.
After about a month in the main tank, one of the Neons developed a white lump on both sides of the tail on the red part. These grew very slowly for about a month and another smaller lump developed on its side, closer to the middle of its body. Once or twice one of the lumps seemed to exude a white substance which then went after a day or two but the lump remained. Otherwise the fish swam, ate and behaved normally. Eventually, the lumps got wider and the fish started to have trouble breathing but was still trying to eat etc. I decided to euthanise with clove oil. This was a week ago. Just today, I noticed another neon has developed a small but telltale white lump in the same red pigmented area. I don't know what to do as I have no idea what it is. Fungus, Columnaris, neon tetra disease,
<This likely: Pleistophora hyphessobryconis>
I've looked them all up but none of them really fit. Because of this I did not medicate as it seemed like I was firing in the dark. If you have any advice or just a hunch as to what it could be I would really appreciate it.
The worst thing is that it doesn't really fit any one disease That are common to neon tetra.
<See here as an example:
Bob Fenner>

Re: Help with neon tetra      6/16/17
Thank you for your quick reply.
Could I just ask you, if it is Neon Tetra Disease, can it infect my other fish, being cherry barb, emperor and phantom tetra?
<Unfortunately, yes. More likely the other Tetras, but the Barbs as well>
Also, I assumed it was a very fast acting disease, killing the fish quickly, so in my case can the disease be chronic, and take over a month to kill the fish?
<At times; yes>
Many thanks,
<As many welcomes. BobF>

Cannibalistic neon tetras.... No.    4/10/16
Ok so I had 5 neon tetras, but after a few days I had to return them.
Everytime I had fed my fish I would make sure to make some food fall to the bottom, because they're near the bottom, but they'd never eat any,
<.... What are the water conditions here? pH, hardness, temp.? Are there measurable metabolites? What numbers?>
they'd see it swim up to it, look at it, and swim away. After 3 days of having them I had come home and found 1 dead, so I returned it and got a replacement, but when I had gotten home I found another one dead, and 2 wounded. Now the 2 wounded looked like a fish had eaten part of it,
because one had its whole top fin missing leaving a chunk of skin exposed and a part of its tail missing, he soo died. The other one had a piece of its top fin missing also, but not to the extreme of the other one. I had 2 Molly's with them
<Incompatible.... need very different water conditions. SEE as in READ on WWM re both
but I had fed them before I left to return that you dead fish, and they mainly stay at the top of the tank, they didn't bother the tetras at all. I believe the tetras had a fight or went cannibalistic on each other.
<No; you' re killing them>
Does that actually happen with blue neon tetras? What do u think happened? What could I have done better? Or how could I have prevented this?
<Reading, understanding what you're up to>
Side note: when adding fish into the aquarium I do leave the bag 20 minutes, then add, little by little, my aquarium water into the bag so they can get adjusted to it, and not stress as much. I also wait 10 minutes in between adding more water, to prevent stress.
<If there's measurable ammonia, higher pH in your system than the shipping water; they're being poisoned by this SOP. Bob Fenner>

neon tetra, too few in too small a world - 8/17/12
I have 2 neon Tetras
<Won't be happy in groups of less than 6; these two will pine away, ignore their food, eventually die.>
in a 5-gallon tank.
<Too small for Neons. How long has this tank been set up? How did you cycle the filter before adding the fish? If the tank is new, and the filter wasn't cycled (with a source of ammonia) for 4-6 weeks before buying, adding the fish, then it's almost certain you have non-zero ammonia, nitrite levels, and these are stressing, killing the Neons.>
The pet store recommended a tropical granule with color enhancers as the only food.  When I drop a few granules into the tank, the fish swim all around them, but do not go after them or eat them.
<Not at all surprising.>
They then lay on the bottom of the tank.
<Remove these.>
The granules seem too big for their small mouths. Will they munch on those granules on the bottom or do they need a floating food?
<Neons need foods that sink slowly, e.g., a good quality flake like Tetra Min.>
Would three neons in a 5-gallon tank be to many?
<6-8 Neons in 10-gallons is the MINIMUM for this species.>
Thank you for any help you can provide.  B.J. Lane
<Glad to help. All you need to do is buy a new aquarium, cycle it for 6 weeks (if you don't have any mature filter media to hand to put inside the aquarium filter), then add the Neons. Do read:
Cheers, Neale.>

Tetra with white mouth  2/5/11
Dear Crew
Just to update you all, sadly, my panda platy died last night from what we are sure was fish TB (mycobacterium). Despite not eating, she lasted a good two weeks on twice daily water changes although her eyesight must have failed her and her tail became covered in fungus in the last two days - very sad.
I've got two neon tetras now waiting some sort of help. They have had this white patch on their mouths - curiously, it's been developing really slowly over the past two months and they appear to be normal/eat normally. I've now put them in the hospital tank with their tank water, air and heating.
I've not added any treatment at this stage as I wanted to check what I should use if any. I'm thinking that it is probably Columnaris as I found a few white spots on another tetra a few weeks back when we had a small nitrite spike for a couple of days and which I cleared up with a broad spectrum antibiotic. However, I've attempted to treat this tetra before and its white patch on its mouth didn't clear up. Is it worth treating this one again with an antibiotic or a die-based solution for the Gram-negative bacteria?
Many thanks for you excellent help as ever.
<Yes, I agree, Columnaris is probable. But with Neons, this does seem quite a common malaise, perhaps caused by fighting or bumping into solid objects.
Would treat with something like eSHa 2000 that treats Finrot, Columnaris and fungus all at the same time, and beyond that, hope for the best. As ever with Neons, ensure the water isn't too hard and the temperature isn't too high -- these are surely common mistakes that shorten their lifespans in captivity. Cheers, Neale.>

Neon Tetra Fungus? 02/05/11
Hi Crew Again
Hope you had your morning coffee.
I am keeping individual emails per question to make things easier I hope.
I have 7 neon tetras and the one in the picture has had a white growth on his (male I think) lip for a couple of months now. When I first noticed it I moved him to a hospital tanks and treat with JBL Fungol
As he has not got worse I can only assume that what ever it was has been treated.
This morning I noticed that one of the females has developed a white spot on her left side (see pic) I think it may be fungal.
Not sure what to treat her with - I have an array of medication.
Either do a Salt dip.
or JBL Ektol Fluid, JBL Ektol Crystal as well as Fungol2, Punktol I have some Interpet anti bacterial fluid as well.
Many thanks.
<This would appear to be Mouth Fungus, which, despite its name, is a bacterial infection, sometimes called Columnaris (the bacteria species is called Flavobacterium columnare, or in older books, Flexibacter columnaris, hence the name). It isn't difficult to treat when caught early, and an anti-Finrot medications will usually work well. Fungus proper can look similar, but the threads are usually longer and fluffier. Some medications will treat both; I particularly recommend eSHa 2000 because of this, and in the UK and parts of Europe this medication is widely sold an inexpensive. Do remember to remove carbon from the filter, if used, while medicating. Mouth Fungus may be caused by water quality issues, or it may be a result of fighting or some other type of physical damage to the mouth. Review and act accordingly.
Cheers, Neale.> 

Re: Neon Tetra Fungus? 02/05/11
Hi Neale
Many thanks for your reply.
<Glad to help.>
Do you think the female with the white spot just under the blue line is the same?
<Probably not. Could be Whitespot, but for now, the Columnaris is the priority, though the standard salt/heat method against Whitespot could be used safely and without causing stress to your Neons.>
We treated the male with mouth rot about 2 months ago - the white on his mouth is still there but he as not got any worse, should what looks like rot have gone away by now?
<Difficult to say. Bacterial infections may come and go depending on the strength of the immune system, which is why they become killers in tanks with underlying problems. The bacteria responsible are present in all tanks, all the time. For what it's worth, I don't recommend Neons unless you happen to have soft water and you also have the option of keeping them relatively cool; Neons don't do well in hard water and they don't do well kept above 25 C/77 F. Cheers, Neale.> 

Tetra Neons... keeping/killing  1/24/11
Hi, I just got 5 Neons about 4 days ago, and unfortunately one of them has already died. They are in a 10 gallon tank with a pH of about 6.5 and nitrate and nitrite readings are low as well.
<Meaning what? Is this aquarium brand new? A new tank *will* kill Neons. It needs to be cycled for 3-4 weeks at least before adding the Neons. By cycling, we mean presenting a source of ammonia, such as pinches of fish food every couple of days, and then doing the usual 25% water changes every week. If the tank is new, ammonia will be high for the first couple of weeks, nitrite high for about weeks 2 to 4, and only after the fourth week will ammonia and nitrite both be close to (or at) zero, and that's when nitrate starts going up. That's also the point when you can start adding fish. There's no "low" level of nitrite (with an "I"). Any nitrite level above 0 is potentially dangerous, and above 0.5 mg/l there's a good chance of the fish dying quickly.>
The tank is heated to about 79-80 degrees F.
<Too warm for Neons.>
I am concerned that the water may be too hard for them. When I tested the GH it was 180ppm. Is the hardness hurting the fish?
<Can do, long term. But Neons won't die within days because your water is moderately hard. In fact they may well do just fine, provided everything else in your tank is good.>
If so, what can I do to lower it?
<Cheers, Neale.>

Jumbo Neon Tetras
Neons Eaten By Which Fish?   10/14/10

Question: We have an 80 gallon tank, with an old upside down catfish 5 inches long, an old striped Rafael 4 inches long, 2 new severum 2 1/2 inches long, 2 new angel fish about 2 inches long, and we had 15 jumbo neon tetras about 1 inch in size that did well for three weeks and have now been slowly eaten. Who would be the culprits in our tank? Could we be successful with the jumbo Neons if they were 2 inches long?
< Real upside down catfish are only a couple inches long. There are many Synodontis species that swim upside down and could be called upside down cats. The cichlids could be killing them and the catfish picking off the scraps. Larger fish would no be eaten right away but still could be killed..Neons really do better in a tank with fish their own size.-Chuck>

Neon tetra turning white, but acting otherwise normal, likely NTD  09/29/10
Good morning,
<Hello Melanie,>
I need some advice on my poor neon tetra.
<Fire away!>
Here's the aquarium history:
20 gal. planted tank with bog wood, fully cycled since February 2010.
<Sounds good.>
Last tested last night using a Jungle test strip:
Nitrate - about 10 ppm (mg/L) (the colour was pinkish between 0-20 and within the 'safe' zone)
Nitrite - 0
GH - Soft, about 75 ppm
Chlorine - 0
KH - in the ideal range 120-180 ppm
pH - about 7.2
The last water change was about a week ago.
<All sounds ideal.>
Note: the bogwood had black fuzzy material growing on it, so I removed it, scrubbed it, then boiled it in a 10% vinegar solution. Then I scrubbed it again and let it soak in plain water for several days before returning it to the aquarium last Saturday.
<The black stuff is red algae, and scrubbing it won't make much difference either way. Red algae tends to grow in conditions where there is medium to bright lighting but not enough fast-growing plants. Stick a clump of Floating Indian Fern in the tank, and you should find algae becomes much less of an issue.>
Tank inhabitants: 1 rubber lip Pleco, 1 male Betta (he's peaceful), 7 neon tetras, 2 assassin snails.
<All sounds fine, my one comment being that Bettas prefer warmer water to Neons. Your Neons, Rubber Plec, and to some degree the snails will do best kept fairly cool, 22-24 C/72-75 F being ideal. Although not the reason your Neon is sick, this is a common reason why Neons generally have relatively short lifespans in many tanks, a couple of years instead of 4-5 years.>
The Neons are the latest addition, added back in July, and were purchased from a reliable LFS (not PetSmart)
<Unfortunately with Neons, they mostly come from the same fish farms, no matter where sold.>
The fish are fed once daily one of the following: Topfin Betta food, Bettabites, Topfin tropical flakes, Topfin freeze dried blood worms, and Pleco algae wafers. I usually rotate through these. The only exception was back in early September, I gave the fish a 3 day feeder block. I don't normally use the blocks.
<Very wise; they tend to do no more harm than good. Your fish can easily go two weeks without food.>
All fish have been eating well, with some of the fish being pigs and eating too much from time to time.
<Sounds like they're doing well.>
Here's the problem:
One of the neon tetras has recently, over the last few days, developed a discolouration from the dorsal fin, through the colour bands and now to his stomach. I think it started at the colour band and has migrated out, but I could be wrong. The white patches are not fuzzy. The fish appears slightly lumpy - not looking nice and sleek like his brethren. He simply doesn't look right.
<My fear here is that he's tending towards Neon Tetra Disease. This is one or two distinct diseases: some people think it's usually a parasite called Pleistophora, while others thing at least some cases are caused by a bacterial infection. Either way, Neons rarely if ever recover, so euthanasia is usually the best approach. Pleistophora at least is highly infections, and many, MANY aquarists have found that once one fish
succumbs, they lose another Neon every few weeks.>
However, the fish seems to be behaving normally - he is schooling, eating, swimming well, reactive to a person watching the tank. He is not restless or stressed looking, fins are not clamped, not gasping for air, not glancing on rocks/decorations.
<I see.>
I have Googled my brains out and now just have a list of possible maybes that each require different treatments. Is it Columnaris?
<This is usually distinctive, with growths around the mouth, but to be honest with Neons being so small, detecting such features is hard.>
Neon tetra disease?
<I fear as much. NTD is characterised by loss of colour, loss of appetite, a tendency not to school with the other Neons, shyness, bloating, and eventually death.>
Muscle death due to invisible parasites/flukes?? I just don't know!
<Nor do I.>
I will take a picture and send it as soon as I get home tonight.
<Very good, this will help. Do note our preference for a sharp photo no larger than about 500 KB.>
My current plan is to buy a 2.5 gal kit with heater and filter to use strictly as QT.
<That would be very wise. If handled this way, you might try using a broad antibiotic and hope for the best. If you decide to euthanise the fish, read here:
The clove oil method works extremely well with small fish, I finding a litre of water with 30 drops of clove oil does the job quickly and painlessly.>
I will take Mr. Yucky out tonight and await further instructions... Please let me know if there is anything else I can tell you.
Thank you!
<Hope this helps. Cheers, Neale.>

Re: Neon tetra turning white, but acting otherwise normal 09/29/10
Thank you very much Neal for the quick response.
<Always happy to help.>
I will make some changes to the tank as suggested (always looking for an excuse to add more plants). I also keep the temp at 76 - at the high end for tetras and the low end for Bettas. I guess nobody's happy.... maybe I should move the Betta into his own home.
<Would be wise.>
As for the sick neon: he was quarantined last night.
<OK; but if he's merely injured, this could cause stress, and that in turn will make him less rather than more likely to get better.>
I'd like to try medicating first as the fish doesn't appear to be distressed as of this morning. However, I already own clove oil and am prepared to euthanize if things don't improve.
My next big worry is this: what should I do with my main tank now? Is there anything I can do to ensure that the others don't come down with the same illness?
<Prayer? In all honesty, Neon Tetra Disease is very difficult to eliminate from a school of Neons, and it's more about ensuring optimal conditions and removing infected fish than anything more "medical".>
I plan to do a water change tonight (the usual 20-25%) and replacing the carbon filter (long overdue).
<Do bear in mind my usual advice that carbon removes medications and is also fairly useless in freshwater tanks. If you don't have a specific reason to use carbon, the space in the filter would be MUCH better used for more biological media.>
Thanks again,
<Cheers, Neale.>
Re: Neon tetra turning white, but acting otherwise normal 09/29/10
Sorry, didn't see the response to this email until after sent the last one... see what I mean? Weird!
<Indeed. The thing with Neons and many other transparent fish is that damage to the skin or muscles makes them opaque. If the whole fish is opaque, that usually means they're very ill, but if it's just a region,
then you may be dealing with something more like a bruise.>
This fish hasn't been touched by a human since he was first placed in the tank back in July. Last night was the first netting for him in a while. I was suspecting he'd been hurt by decorations (the bogwood is kind of pointy in spots) or by another fish, but wasn't sure.
<Bogwood shouldn't be a problem as such; Neons come from habitats with lots of things they might bump into, yet manage just fine. On the other hand, fish can bump into things -- including the glass and hood -- when alarmed, including when lights are turned on, so a good tip is to turn the room lights on a few moments before turning the tank lights on. The reverse is helpful at night when you're switching off the aquarium lights.>
I just fear having all my fish wiped out due to ignorance on my part.
<I wouldn't worry about that. For what it's worth, Neons are one fish I've never managed to keep alive for long. The quality of Neons in the trade is, unfortunately, rather low.>
I'll keep him as is, isolated. I won't medicate for now. Is there anything you'd recommend that I feed him for a faster recovery - or just the same old flake?
<Pretty much.>
Is a product like stress coat of any use in a situation like this?
<Won't do any harm, so if you have some, sure, use it. But I wouldn't rush out to buy this or Melafix or whatever.>
Crossing fingers! Thanks again,
<Glad to help. Good luck, Neale.>
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