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Astronotus ocellatus (Agassiz 1831), the Oscar. To seventeen inches (45.7 cm). South America: Rio Amazonas basin in Peru, Colombia, Brazil, Northern Paraguay and French Guiana. Freshwater: pH range: 6.0 - 8.0; dH range: 5.0 - 19.0, temp. 22 - 25°C. Wild type at  the Shedd Aq. 2015 
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Freshwater FAQs, Ask us a question: Crew@WetWebMedia.com

Updated 11/21/2018
Other Specialized Daily FAQs Blogs: General, Planted Tanks, Ponds, Brackish, Last Few Days Accrued FAQs,
Daily Q&A replies/input from the WWM crew: Darrel Barton,
Neale Monks, Marco Lichtenberger, Bob Fenner, are posted here. Moved about, re-organized daily Current Crew Bios., Not so current Crew Bios

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Betta Success
Doing what it takes to keep Bettas healthy long-term

by Robert (Bob) Fenner

Unknown Betta Issue      11/21/18
My Betta fish has become increasingly sick throughout the past couple of months. I have tried a new filter, bottled spring water,
<Mmm; need to know about this... pH, hardness especially. You may be missing useful mineral content here>

stress coat, salt treatments, frequent water changes, Kanaplex and fungus clear, cleaning the entire tank and turning the heat up. Nothing I have tried seems to help, he continues to get worse. He still eats,
<What? Have you read on WWM re Betta health? Care?>
swims around and flares. He does not seem to be impacted by this much.
I have attached photos below from when it began until now.
Thank you in advance for any suggestions you have as to how to treat this or what it might be.
<... Please respond to my concerns above. Bob Fenner>

Last Hope for my Betta     11/21/18
I have a 2 year old Male Betta living in a 5 gallon planted, heated tank with a sponge filter. I am guilty of falling behind on cleaning the substrate and I think that might be to blame for his current condition.
<Oh? Do you use nitrate concentration as a guideline here?>
About 2 weeks ago I noticed he was unable to "catch" his food(pellets). He would keep trying and missing. I foolishly ignored this.
For the last 3-4 days he has been laying on his side at the bottom of the tank. Yesterday I moved him into a shallow "hospital" tank. I thought it was just his time to go at first, but his condition has lingered too long for it to be a natural death (I believe). He has no signs or symptoms other than previously mentioned.
Is there anything I can do for him?
<Yes! Check your water quality; switch out a good deal (like half) of the system water for new (best from another established aquarium); and add in a bit of frozen/defrosted food to the fish's diet>
If not what is the best way to euthanize him?
<Mmm; I am hesitant to suggest this at this juncture. I'd hold off. This fish may well rally... return to robust health. IF you feel otherwise, please read Neale's piece on the topic:
I can't let him suffer like this much longer. Thank you for your time and consideration.
<Cheers, Bob Fenner>

Re: Fwd: Last Hope for my Betta     11/21/18
<Little Dani>
Thank you for the fast reply! I gave up my tanks and all of my water testing supplies a while back. I adopted this Betta from a poor situation after the fact. Yes, I feel confident that nitrates are to blame for the issue. I am keeping the water in the hospital tank "safe" by using Seachem's Prime. I did acclimate him very slowly when switching over. I've rehabilitated fish in the past this way successfully.
<I see>
If he pulls through, I will absolutely make the diet changes you suggested.
As for right now, he is showing no interest in food whatsoever.
<Too likely there are "cycling issues" w/ the current situation. Just adding Prime won't do... I'd place this fish back in its water changed system w/ the filter, substrate...>
Is it safe to assume that the best course of action is to keep him in the shallow tank, continue daily water changes and hope for the best?
<No; see above>
He has been without food for at least 4 days, but probably longer since he was having trouble catching his food before turning lethargic. My fear however is that he is slowly and painfully starving to death :'(
Thank you again,
<Welcome. BobF>
Re: Last Hope for my Betta     11/21/18

Will get on that right away. I just got home and noticed that he is looking a little "bloated" now. Is this a clue to a different issue?
<Likely all related to environmental stress. IF biological, secondary in origin. Bob Fenner>

Crayfish turn green after moulting     11/20/18
Hey WWM,
<Howsit Darren?>
My female crayfish (Cherax quadricatinatus/red claw crayfish) moulted today and her head turned from her usual brownish blue colouration to a moss-like/grass-like green colouration. I tried searching for answers online but nobody seems to have indicated that their crayfish have turned green (only turn blue/brown). Do you know what might have caused this?
<Mmm; yes... "know" as in high enough confidence in my interpretation of facts/evidence>
My water parameters are good and she is living quite comfortably in her 10 gallon. The tank is very sufficiently aerated (you can even see bubbles in the water) and she is given algae wafers and traditional crayfish pellets.
Could it be the algae wafers (which was the only food she would eat prior to her moulting) or could it be something else?
<Such color changing, difficulties in moults are most-often due to nutritional and environmental (water quality) issues. These crayfish need some protein from animal sources, iron and iodide/ate... and a setting with sufficiently hard, basic water.
These requirements are gone over and over on WWM.
Provided all, your crayfish may well change shell color in time, with successive moults. Bob Fenner>

Re: Crayfish turn green after moulting     11/21/18
My water's pH is 7.8 and her crayfish pellets should be giving her sufficient protein.
<I'd still be supplementing w/ a bit of animal source; AND iodide/ate added directly to the water weekly>
I think she's fine but I'm just shocked to see a bright, almost grass-green colour on this species because usually they don't turn green.
<Mmm, I worked quite a bit w/ Procambarus clarkii in college, and on my own...
Crayfish can/do occur, change in shell color quite a bit... genetically, via env. and nutritional influences. Bob Fenner>

Amazing Website!     11/18/18
Wow, I am learning so much from your website.
Mostly, I am learning that I've been doing everything wrong!
<Oh dear. Well, I guess this is what they call a learning curve...>
I have a Betta who has been behaving very sluggishly. He's actually been "holing up" at the bottom of the tank, in a little "cave" made by the stones on the bottom.
For the past 2 days he didn't come out and I was sure he'd died. But no, today he's been swimming around and I was able to feed him. But this can't be normal behavior?
<Not really, no. Fish will often be reclusive for a few hours to a couple days after being introduced to a new tank. But if they're persistently shy, beyond what they should normally be like, then there may be something frightening them. Sometimes, it's bright light or unnaturally coloured substrates (such as white gravel) that alarms them. But other times it's the water chemistry. Fish will respond to non-zero ammonia and nitrite levels by behaving as if they're scared. It's kind of like when cats are sick and they hide. They don't "know" they're sick, they just feel pain,
and their instinct when scared is to hide. Fish do the same thing.>
I've been speaking with Petco, who recommended bringing the water in for testing, and they said it was just fine.
<I would suggest letting us have the numbers. Get a water test kit, at minimum, a nitrite test kit. Non-zero nitrite (or ammonia) levels are dangerous, potentially lethal after a few days.>
But now I'm reading on your blog that "just fine" isn't good enough, you need me to tell you the actual numbers.
So I need to get my own test kit. What do you recommend?
<They're all much the same chemicals, so doesn't really matter.>
I've also been told to do a 50% water change once/week, but what about what has settled in the stones at the bottom? Doesn't that need to be cleaned?
<Not beyond stirring gently before a water change, and then using that water change to siphon out any muck.>
I don't have a filter. Should I have one?
If so, what brand to you recommend?
<Again, doesn't really matter. Small internal canister filters from the likes of Eheim, Fluval and other well-known brands all do the job well. The Eheim ones are probably the best in terms of long-term reliability, easily running 20+ years if cared for, while the generic Chinese ones will do the job, but seem to fail after a few years. So it's really down to personal preference and budget.>
I do have a small pump which creates air flow, and of course a heater.
<A simple box filter or sponge filter can be connected to the air pump.
These would be perfectly adequate for a Betta, which actually prefers little water current, so an internal canister might not be the perfect choice if you can't tone down the water flow rate.>
Two heaters, actually, since my house is quite cold. It sits at about 74 degrees in the fish tank (which is 2.5 gallons). Is that warm enough?
<Long term, no; Bettas really need a consistent 25 C/77 F, and more to the point, cold air kills them -- they're air breathers. So make sure the tank has some sort of hood to trap warm air. I can't imagine why you need two filters unless they're really poor quality. Assuming this is a 5 gallon tank -- the absolute minimum for "easy" Betta keeping -- then something like a 50 W heater should be more than adequate.>
<Cheers, Neale.>
Re: Amazing Website!     11/19/18

Wow, thanks for the lightning-quick response Neale!
<Most welcome.>
For me, it all started with this:
https://backtotheroots.com/collections/top-sellers/products/watergarden So I guess my first problem is that the tank is only 3 gallons. So this is really not sufficient?
<It's tight. Here's the deal. While Bettas *can* certainly live in tanks this size, the margin for error is much less. The water cools down faster if the heater fails, the water quality worsens faster between water changes
(let alone if the filter dies) and there's less volume to dilute overfeeding if you have someone look after this fish in your absence (something almost never worth bothering with -- fish can go weeks without food). Given that a 5 gallon tank is still tiny, and won't take up much shelf space, but offers up nearly twice as much water as you've got now, it's still a worthy upgrade for the future. I'd also observe that 'hiding' a heater and a filter in a 5 gallon tank is much easier too, because you'll have more space for plants, rocks, etc.>
I quit trying to grow the seeds because they leaked into the tank and made a huge mess, so now I am just enjoying my Betta fish!
<Seeds? What seeds? For what it's worth, it's not worth bothering growing aquarium plants from seed.>
He's been in that tank for about two years, so there is nothing new that could be scaring him.
So it's back to water quality. I will get a test kit today. In the meantime, I just did a 50% water change.
I keep a lid on the tank to retain the heat, but the temp is never 77 degrees as you suggest below. It's more like 74. I live in Colorado and my house is pretty darn cold! So I will get a new heater today too.
<Assuming you've got central heating in this room, the air temperature in the room shouldn't really be much colder than, say, 20 C/68 F. If you look on the back of many brands of aquarium heater, there are tables describing
what wattage you'll need to elevate the water temperature 5 or 10 degrees above ambient room temperature. You can find these tables on line, too.
Anyway, something around 50 W should be ample for a 5 gallon tank, even if you need to raise the temperature a full 10 degrees above ambient room temperature. Don't go overboard though, and get a really high wattage, as
these may heat the water immediately around them much too quickly.>
I read about gravel siphoning devices somewhere on your website. Do you like those, or just a regular filter? Or both?
<I'd skip the gravel siphon. It's a device to facilitate water changes, sluicing the gravel through the water being sucked out. While quite useful, they'd be much too big for a tank the size of yours. A simple turkey baster
(new, or at least well cleaned!) can do much the same thing if jetted into the gravel at a few places, and any muck that emerges can then be sucked out with your standard issue hose pipe of the sort (I assume) you use for
water changes. Note that water changes complement filtration. They're not an either/or. Yes, Betta breeders keep their fish in jars without heaters or filters. But those jars are emptied each day, and the fish room is heated to keep the water at upwards of 25 C/77 F all day long. Much too expensive and labour intensive for a hobbyist!>
Thanks for the info about Betta's not liking a strong water flow. Thanks
for all the info!

Help with black mollies     11/11/18
I have 2 black mollies I think one male one female one of them the skinnier one will sit at the bottom take a little bit and then held swim up and swim next to the other one and he let himself float down to the bottom of chain sit there for a little while and the other one is way bigger than the other ones skinny ones having the problem or if it is a problem I don't know but I'm just wondering if it's normal behavior or if it's something I should be concerned about
<Hello Mike. Let me have you do some reading first:
The thing about Mollies is that they're a bit disease prone when kept in plain freshwater. Certainly, hard water is better, and ideally, a reasonable amount of salt, maybe 2-3 teaspoons per US gallon, can make all the difference. On top of that, they're often maintained poorly by retailers and wholesalers, and the quality of farmed Mollies is very variable. So it's a bit hit-and-miss whether you get healthy ones or not.
Understanding their specific needs will help a lot. So yes, I'd be worried about a skinny Molly that wasn't swimming properly, but before medicating, I'd be checking water chemistry first. Simply maintaining them in saline conditions can make all the difference! Cheers, Neale.>

Baby Oscar      11/10/18
I have two 6” Oscars in a 125 gallon I just hard reset to give them each a territory with lava rock and driftwood, caves with plastic flower pot liners inserted into siliconed rock surrounds, etc.
<Indeed; if these are two males, there's a good chance they WILL NOT cohabit in a tank this small once mature. I know 125 gallons sounds massive, but bear in mind that an adult male Oscar will be guarding a territory with a radius of some 6 feet around its spawning pit. For sure they'll sometimes ignore dissimilar tankmates, but a rival male Oscar has almost no chance of being tolerated. Observe both fish carefully, and be aware that fights can easily result in injuries that are very difficult to treat. The classic ones are eye injuries (which lead to pop-eye or blindness) or most distressingly, dislocated jaw bones. Once the jaws are damaged, usually through wrestling, the jaws never heal, and the fish starves to death.>
I have 2 HUGE canister filters and a HOB and will be building a fluidized bed sump when the rest of the parts arrive next week.
They are doing well, growing around 1.5” a month, love people (and haven’t even eaten the sacrificial plants I threw in there for entertainment). They get 25% water changes every other day and are water tested everyday. So, in short, I am a little familiar with the species. Today, while out grabbing some supplies for the house the hubby and I saw an inch and a half Oscar in a tank full of 3-4 inchers. It was in a store we all go to, but preferably NOT for fish because their tanks have a super-high mortality rate.
I knew what would happen if we left him there.
Sadly, I think we all do.
<Yes; but the flip side is plenty of animals much smarter than Oscars are bred and die on an industrial scale for human uses, such as pigs. Once you buy a pitiable fish, yes, you're saving that fish, but the retailer simply sees this as a successful sale and orders another. So while the humane act would seem to be rescuing such fish, in reality what you're doing is encouraging the overproduction of large, difficult to house 'tankbuster' fish. The logical thing to do is ignore the fish, and yes, it'll die, but the retailer won't order it again given money was lost on it. Make sense?>
So, I brought him home, knowing full well the mess of filters, water changes and probably the creepy crawlies he was bringing home. My friend owns a pet shop, so we popped by and threw together a 10 gallon hospital tank. We filled the tank with pre-heated, oxygenated R/O,
<Do be careful about making "good" water chemistry changes all of a sudden. If this beast was in hard water, slapping him in moderately or very soft water could do more harm than good. Best thing with water chemistry changes is to do them across several days.>
slapped in a filter with cycled media, air and lights (kept low to keep him calm). I set the temp to 84F and am giving him the first round of Paraguard. I know its probably stress, but he’s not eating. Is there anything I can try to tempt him with that isn’t crushed pellet, homemade frozen or pieces of prawn? Anything you think I should know about caring for a guy this young?
<Earthworms and small river shrimps are crack cocaine for Oscars, so these'd be my go-to foods. Earthworms are usually safe because they're unlikely to be exposed to water parasites. With shrimps, ideally gut-load them with flake food first. Frozen shrimp is okay, but remember it contains thiaminase, as do mussels, so long term causes serious health problems if it isn't used alongside thiaminase-free foods such as cod fillet, cockles and squid.>
(Oh, and please set your mind at ease about his future, I’ve already got a mailbox with his name on it outside the new 55 gallon tank sitting on my living room floor for this guy. �� )
Thank you so much for this site, when I first decided on Oscars, I read everything I could get my hands on, and I spent a ton of time here. I promise never to ask about the sex of an Oscar, lol.
<Indeed! Virtually unsexable.>
Thanks for all you do,
<And thank you for the kind words. Cheers, Neale.>
Re: Baby Oscar     11/11/18

Thank you, Neale for all of your help.
<Most welcome.>
Yes, the 125 could turn into an issue. I bought the two larger as a shoaling pair. As juveniles, they have proved inseparable. Of course, that can change any day as they get older.
<Precisely. Juveniles are social, even, as you say, to some degree schooling fish. Presumably this is some sort of defence against predators. As they mature, this will change, and pairs of sexually mature fish will claim territories and drive away other Oscars. Very similar to most other monogamous pairing cichlids, e.g., Angels.>
There have been some displays of dominance like lip locking, but it hasn’t happened often.
<Good. Every Oscar is different, and they're intelligent animals with behaviours that can, to some extent, adapt to their environment. So I'm quite sure that sometimes two 'brothers' end up living together more or less amicably. Just don't bank on it!>
There have been mating type behaviors, though, too… (tail slapping, rubbing up against one another and cleaning a corner of the tank floor). They still actively shoal at 6”. So, at this point, young as they are, it’s a tough call. I have a cycled empty 55 on standby (hospital tank) so if things go south, I at least can separate them.
And you’re right about the baby. I shouldn’t have bought him. I don’t want to encourage the poor husbandry. I can’t go to those places.
<Totally understand your feelings and actions. Not saying I wouldn't have done the same -- but logically, as hobbyists, we would do the fish (overall!) a service by not patronising the scummy stores, and not buying the fish that shouldn't have been imported.>
He’s still not eating, but I will keep trying.
<Oscars (like virtually all cichlids) will eat when they're ready, and not a moment before. Assuming he's not in terrible shape, I'd simply focus on giving him quiet, darkness, and good water conditions. If live river shrimp are available, by all means stick a few in the tank since they're stay alive until such time as he eats them, so won't adversely affect water quality. Otherwise, feel secure about waiting a few days, even week or two before offering meals and seeing them eaten.>
Its hard to say, Oscars are wonderful sad sacks and have a tendency to “mope” when things change in their tank.
<Precisely. It's the flip side of their high level of intelligence. Just as with any other smart animal (dog, parrot, pig) that's been abused, they're not going to suddenly eat food just because it's there. It's Guppies and other mindless fish that do that! No, with these big, cuddly cichlids you need to get them on side first. Calm them down, get them feeling secure, and train them to recognise you're not a threat but a friend. Takes time, and repetition. For example, walk past the tank, say "hello", then walk on, without causing a disturbance by turning the lights on or opening the hood. He'll probably stay hiding, but so long as he doesn't dart away in panic, then it's steps in the right direction. Soon enough he'll figure out you're harmless, and since Oscars, like Goldfish and Koi, genuinely enjoy human company, he'll start seeing you as a friend and come to the front to see what's going on. Once that happens, offer a small, tasty meal. Bit of white fish fillet, an earthworm, whatever. Only a tiny bit, because it might not be eaten, and whipping out a net to remove multiple or large chunks of uneaten food will terrify a nervous fish. I find a turkey baster a great tool for removing small bits of food in a discrete manner.>
Or they don’t get the food they want. Or they haven’t seen you in a day. Or if its Tuesday. He was swimming around this morning, but has gone back into hiding during the day. My guess is he is trying to be sure there is nothing in his tank that would eat him. I tested his water, offered him food and left him alone for the most part. I will continue to offer food.
Thanks again!
<Hope this helps, Neale.>

Tetraodon miurus availability     11/8/18
Hi Neale!
<Hello Nathaniel,>
How are you?
<Just fine, thanks.>
I have been looking for a few months for a Miurus (Congo/potato puffer) to add to my collection.
<Nice fish. Doesn't do much, but not difficult to keep.>
I have a tank that has been ready and cycled for a while now, but the Congo puffer season is nearly over and nobody has had them in!! I'm worried that the season is nearly over and I'll have to wait another year!!
<Quite possibly.>
I've even tried Keith at wildwoods and he's due some but as always with shipments from Congo it's proving tricky.
<I believe the civil war might have something to do with that.>
Do you happen to have come across any shops/individuals who are selling these currently??
<Well, the TropicalFishFinder.co.uk database suggests Wildwoods has them in stock. But that might not have been updated in a while. In which case, I'd have a quick peruse of the PFK readers' favourites from 2017, here:
The top scoring stores there are probably the ones to get in touch with first of all, Wharf Aquatics for example being regarded as the best store for oddballs (and indeed a very highly regarded store within the UK hobby).>
<Hope this helps, Neale.>
Re: Tetraodon miurus availability     11/8/18

Thanks Neale, I already tried all top 40 from PFK but no look :-(
Wharf are looking out but also struggling.
If you happen to come across one then please can you let me know :-)
Thanks again
<Your best bet might be social media. The Puffer Forum is a good place to start, but somewhat US-centric. If you use Facebook there might be groups of interest (I'm afraid I don't know any). One thing with social media is you can offer to rehouse an adult fish, which may be welcome if someone wants to change their focus or have to downsize their collection.
Maidenhead Aquatics is one chain of stores that routinely takes adult fish in and rehouses them, but I don't know if they have a central network that'd allow you to get in touch with all the branch managers
simultaneously. Worth asking, though. In any event, if Keith at Wildwoods can't get something -- it's probably not in the wholesale trade at the moment. He's really very, very good at this. Cheers, Neale.>

Sick Jack Dempsey     11/7/18
I hope you can help diagnose this problem for me. I left my fish in the care of a friend while I was away for 3 weeks, and upon returning, the poor guy was almost dead :(
He is alone in a 75 gal. tank at 78 F. He has developed a very large white growth on his underbelly, lost most of his blue colouring, and won't eat.
There was a lot of uneaten, rotten food at the bottom of the tank. I immediately changed out half of the water, removed the rotten food, and put some Nox Ich in the water in case it was a fungus.
<Nox Ich has no impact on fungus. It's a Whitespot medication.>
Is there anything else you would suggest? He's an elderly fish of 12 or so, so I hope I don't lose him yet!
<A fair age of a JD, so well done!>
Thank you,
<Tonja, hard to say what the problem would be. But I'd be using Metronidazole alongside an antibiotic (Nitrofuran works well in this situation). Alongside these two, I'd be doing regular water changes,
increasing aeration without adding too much turbulence, and laying off feeding the fish for at least a week. Good luck, Neale.>

I.D. Corydoras catfish       11/4/18
Hi, I hope you could help with an id on a Corydoras I picked up recently.
<Will try.>
The closest I could find was C. copei.
<Corydoras copei is rare in the hobby. Though I agree, it certainly looks similar in terms of markings. With that said, many species in this genus are notoriously difficult to positively identify. Books have been written on the subject (such as Fullers & Evers 'Identifying Corydoradinae Catfish') and several names in the trade are almost certainly used for the wrong fish (most if not all "Corydoras julii" are probably Corydoras trilineatus, for example). By the same token, Corydoras copei is quite similar to a number of other species, including Corydoras punctatus.>
Apart from the black in the dorsal the most distinctive feature is the black line which runs down from the eye but there is also an electric blue line that runs along side it. Also there is a black spot that appears on
the body just before the caudal peduncle, it comes and goes depending on mood.
<This latter feature is characteristic of Corydoras punctatus, but also appears on Corydoras copei, Corydoras acutus, and a few others.>
<I do think your guess is a good one, but would suggest positing somewhere like the PlanetCatfish forum where an expert on the genus might be able to help. In the meantime, rest assured that this species has all the same requirements as the vast majority of Corydoras; to wit, low-end tropical temperature (22-25 C/72-77 F) water that isn't too hard (1-15 degrees dH, pH 6.0-7.5) and not too deep (ideally 30 cm/12 inches at most). Keep in groups, on a soft, ideally sandy substrate, and provide brisk but not turbulent water current. Avoid nippy tankmates, but otherwise mixes well with community fish. Cheers, Neale.>

Re: Hello!     11/2/18
I can't believe I didn't attach those pics! I was really sleepy when I emailed lol. Sending now and looking into Microsporidian and see what I can find! Thank you.
<Oh! Another possibility is that these spots are resultant from reproductive, hormonal cause... "Nuptial tubercles"... These too shall pass if so. BobF>

Re: Hello!     11/2/18
Wow! Never heard of that! I will look into that as well thank you! I'm just glad that it will pass if so. I am rather attached to my fish and was really worried.
<I sense/d this; and am glad for it. These organisms are dependent on our care entirely.>
Especially considering that they are genetically altered. This has been my first time owning fish that have been altered in such a way.
<Aye; a bit of "jellyfish DNA" clipped on eh?>
They have been much healthier than I originally thought they would be with no losses as of yet. Quite hardy and comical little guys. Thank you very much for the insight!
<Glad to share. Bob Fenner>

Hello! /Neale     11/2/18
First I would like to say that this website has been a complete obsession almost for any little thing that I ever seem to have questions about. I haven't had to actually write more than once before now. You all are lifesavers! Literally. With this particular situation though I am completely stumped. I have gone through everything I can on here and have not found a match yet that I can see. I will start with a bit of history, not too much though and water parameters. This is a 30gal long, planted tank. Everything from stem plants to floating hornwort. Home to a shoal of 6 albino Cory's ranging from 1-3 1/2 years of age. A school of 6 Glofish (skirt) tetras also ranging the same age. A small school of 6 Glolight tetras. A pair of juvenile peacock gudgeons and a male Betta that is a little over 2 years old. Water parameters are in ppm... 0 amm, 0 nitrite, less than 10 nitrate, GH around 80ppm, KH around 50-60ppm and PH ranges between 7-7.2. I do use peat moss and air stones in my 20gal water tank that I keep cycled and full for water changes as my water here comes out a hard 280-300 GH, about 120-150 KH and a PH of 8.4-8.6. I top off with a mixture of distilled and spring water. My question is about one of my older tetras. She has developed 2 odd pimple-like spots on her but they have come up from under her scales and pushed them out. Its hard to get a good pic of as her scales reflect back the light and the 2 "whitehead" looking bumps are under. She is about 3 1/2years old and roughly the size of a 50¢ piece. She acts completely normal and is eating normally and such. I first noticed these 2 bumps about a week ago and they don't seem to have gotten bigger or gone down any. I thought maybe some kind of parasite but nothing I have read about sounds like this. The only new fish to the tank within the past year are the gudgeons and they have been added in the past month. They have settled in nicely and seem healthy. Idk if they could have brought something with them or if its unrelated. I am attaching the best pic I could get but getting her holding still enough for any length of time to take a pic is not an easy task. Any thoughts or help/advice is greatly appreciated! Thanks, Allie.
<<Bob's covered the basics, but will add an observation re: Hemigrammus rodwayi, the Gold Tetra. This species is actually silver in colour, but the ones in the trade are infected with a non-lethal trematode parasite. I believe this happens naturally, in the wild, rather than a manmade thing. Anyway, the parasite causes the skin to secrete extra guanine, and that forms metallic gold patches, hence the common name of the fish. Praziquantel and other antihelminthic medications have been used successfully against trematodes, though in the case of the Gold Tetra the fish itself appears to be unharmed so such treatment is rarely, if ever, done by home aquarists. Still, it's an option. Of course first of all I'd be treating as per Whitespot and Velvet, just in case either of those (or some similar ciliate parasite) are to blame. The old salt/heat method can work very well, and has minimal toxicity if done correctly. Otherwise, if the tankmates aren't sensitive to standard anti-Whitespot medications, you could try a couple runs of those (Velvet in particular seems to need two courses to be thoroughly dispensed with). Good luck, Neale.>>
Re: Hello!     11/2/18

OK, I don't have any salinity in the tank at all as the Cory's don't seem to like it.
<Soft water fish, including Corydoras, are just fine at the 2g/litre used to treat Whitespot. Just as a reminder, other medications often include copper sulphate and formalin, which are FAR more toxic than salt, particularly to catfish and loaches. Hence the old salt/heat method remains a very useful approach for handling Whitespot and Velvet in situations where other medications aren't an option. Do also note than 2g/litre IS NOT brackish water, and furthermore, the salt/heat method operates over a week or two. A lot of people get confused by the salt dosage, and assume it'll turn the tank brackish. It really won't.>
I do have both the API Aquarium Salt ( just incase ) and Instant Ocean ( I have a low end brackish set up on another tank ).
<The API tonic salt is the one you want. While the Instant Ocean salt would work, it'd also raise pH and hardness. Plain non-iodised cooking salt, or some aquarium specific alternative, only affects salinity, and has no impact at all on pH and hardness.>
I can treat with if necessary. The temp stays between 76-78°.
<Traditionally the temperature is knocked up a few degrees to speed up the life cycle of the Whitespot or Velvet parasite. Once mature, the motile stages burst out of the fish, allowing them to swim about looking for a new host, but crucially, this is THE ONLY stage at which they can be killed. They have little tolerance for salt, much less than fish, so the salt added to the water kills them. Anyway, 28-30 C/82-86 F is considered optimal for the heat/salt technique. Since warm water has less oxygen than cold, you need to up the aeration during the process, or the fish may become stressed.>
I have looked into the velvet and it doesn't seem like that but it could be I reckon and I'm pretty sure its not the Whitespot/ick.
<Velvet tends to be like powdered sugar, often resulting in a golden sheen. Attacks the gills first, so affected fish often gasp, breathe heavily, or look nervous and distressed. Velvet usually progresses extremely rapidly. Whitespot more like table salt, with visible pimples. Often develops more slowly.>
I have had a bit of experience with that over the years but I will definitely be watching close and will treat the tank if other fish start developing whatever this is. I haven't moved her to the hospital tank yet as I'm not sure if that would help or hinder the situation.
I think she would be really stressed by herself but I will do it if its necessary. I did notice today that she has 2 identical spots on the other side in the exact same places. Just not as noticeable. No other spots anywhere else and they are right in a horizontal line almost like its part of her spine or something. I thought the spine was higher up though. I don't have much in the way of meds on hand aside from Melafix.
<Melafix largely useless.>
The ones I had expired unused months ago and I just haven't replaced them yet but I will. I really appreciate you guys taking the time to respond! If you think of anything else please let me know. Thanks again.
<Cheers, Neale.>


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