Panda Cory turning white, and fin rot questions

[stillnzcookie]

Hi, three of our panda corys are not 100% at the moment. I have dosed the tank with acriflavine, which seems to be helping, but one of them has something which I have no idea what it is - I have googled and searched on here, but nothing quite seems to fit.

About 5 days ago, the pale parts of its body went very white, but the black patches stayed very black (so it wasn't just faded all over). For a couple of days that was the only change I could see - it was still active and eating well, but it then seemed to get a bit listless, and the next day I noticed something hanging off the side of its body. The best way I can describe it was that it looked like a blister that had burst and left the skin flapping around, but I had never seen a blister, and I couldn't see any sign of damage underneath. This was when I decided to dose the tank, and the flap seems to be getting smaller, the fish is eating and acting more normally and its colour has returned a bit. So it's all looking promising, but I'm still curious as to what it was. It seems most likely to be an injury, but if it was caused by an injury, I would have thought there would be some sign of damage underneath, but there isn't. Also I can't see why the whole body would go white?

The other reason I decided to dose the whole tank was that the same cory plus two others have a bit of what I assume is fin rot. It seems to be an ongoing problem, which I have never medicated for in the past - just kept up with regular water changes. I have always assumed that it is caused by fluctuating pH (which has always been an issue in this tank), and it seems to go away of its own accord usually, but I'm starting to wonder if it is actually caused by injury - all three fish only have it on the very top if their tail fin, so I wonder if they are scraping it on driftwood or something in the tank? Two of them don't seem very bad, but one is now looking quite raggedy. Is acriflavine the right treatment, and is this all I need to do? I think I read somewhere that it is possible to cut off the infected/dead part of the fin, but I'm reluctant to do this unless it is really necessary!

Our tank conditions are as close to perfect as we can get them - ammonia, nitrite, nitrate all 0, pH 6.8-7.0, but we do have a bit of algae in the tank - can algae (or the cause of algae) cause problems?

Thanks!

[Jennifer]

The white that you mention makes me think of localised irritation, and potentially increased slime production - have you added any chemicals to the water recently? Also, healthy fish shouldn't get injured by rubbing their fins on things. Is there another fish that could be nipping them?

If it is fin rot, a good antibiotic will help more than acriflavine which is a topical antiseptic (antiobiotics kill bacteria from within the fish, antiseptics halt bacterial multiplication on surfaces). Some good antibiotics to try would be SMZ TMP (sulfa trimeth), erythromycin or tetracycline although there are many other suitable options. You will need a prescription for antibiotics.

With any wounds, you should aim to keep very clean water to promote healing. Fin rot can sometimes be caused by poor water conditions. It sounds like you have been very careful with water chemistry but I would also take care not to overfeed, especially now. It wouldn't hurt to do a good vacuum of the substrate to remove any rotting food or detritus that could potentially be contributing to the problem. Keep up with the water changes, up to 30% daily wouldn't hurt if your fish can tolerate it.

[Zev]

Have you been using any ferts?

I know that corys are not partial to above average doses of Flourish Excel :oops:

[Adrienne]

I would agree with Zev or otherwise a heater burn?

[stillnzcookie]

Thanks for the replies.

The white that you mention makes me think of localised irritation, and potentially increased slime production - have you added any chemicals to the water recently? Also, healthy fish shouldn't get injured by rubbing their fins on things. Is there another fish that could be nipping them?

I wondered about increased slime production, but it really looks like the fish has changed colour, not just that it has a white coating on it. No, we haven't added anything to the water (apart from Stress Coat) in ages. We only have cories, harlequins and rainbowfish, so it's a peaceful community tank, and I haven't seen any signs of aggression.

If it is fin rot, a good antibiotic will help more than acriflavine

Will a vet give a prescription for this? How do you give a fish antibiotics? Will I need antibiotics, or is there a chance that it will clear up without them? In the past, it has seemed to clear up of its own accord, but perhaps it has never fully gone away? Two of the fish look like they have before, but one of them seems worse than it has ever been - rather than just a whitish line along the top of the tail fin, it is looking quite ragged.

I know that corys are not partial to above average doses of Flourish Excel

We have not used Flourish Excel for several months, have only used recommended dose, and cories have had fin rot before we ever used it as well, so it's very unlikely to be that. But that is good to know, so thanks!

or otherwise a heater burn?

Heater burn is a possibility, as they all squeeze behind the heater, and often sit there for ages, but it seems unusual that they all have it in the same place. One of them got stuck behind the heater one night last year, and when we rescued it in the morning it had a big white burn right down one side (which fortunately healed very quickly). Actually, I hadn't even considered that that could be what happened to the cory with the funny flap on its body - it could have got stuck and blistered, then freed itself and burst the blister, all overnight But it still doesn't explain why its body turned white two days before that :-?

[phoenix44]

are they slightly red around the gills?

[Jennifer]

Regardless of the cause, it sounds like there are some wounds there, whether or not they are infected is another issue but it does sound a little like fin rot. It would be useful to know the cause so you can prevent it from reoccurring. Also, secondary fungal infections might also be present. These look like white fuzz or black spots and treatment involves different medication.

Anyway, some commonly used broad spectrum antibiotics/dosages are:

Erythromycin 1mg/5l

or Tetracycline 1mg/12L

or Sulfathiazole (either triple sulfa or sulfa trimeth) approx 700mg sulfathiazole/40L

Do a large water change or put the fish into a hospital tank with a good portion of clean water. Dissolve the medication in a cup of lukwarm water, then add it to the tank. Dose once each day at the same time, then after 48 hours do a 25% water change. Keep dosing once every day and doing a 25% water change before each treatment. Continue for 5 to 7 days. Be sure to remove any carbon from the filter (if present). Once the treatment is complete, remove all traces of the antibiotic by adding carbon or putting the fish back in the main tank.

If you take photos of the fish into a vet clinic (preferrably where you have a relationship with your other pets) and show them the photos and explain your situation and the medications you wish to try, they will often prescribe you a course of medications. Keep in mind, less medication is required when you treat a small hospital tank rather than the main tank. Also, these antibiotics will likely affect your biological filter so that is another reason why it is good to use a hospital tank. I personally just use a clean bucket with a heater.

[Zev]

Q for Jennifer, is Stress Coat the one that encourages more mucus production and hemolytic activity by formalin poisoning?

[Jennifer]

I have no idea. That's not a product I have regularly used.

...but causing irritation to encourage slime seems like a round about way to make fish feel better. I tend to think that keeping good clean water is a better way to treat any fish problems, cheaper than adding chemicals too. :roll:

[phoenix44]

stress coat is probably my favourite remedy on the planet!

I swear by it, and salt when fish are injured.

[Jennifer]

I also use salt on occasion but I have mainly used Seachem Prime as a water conditioner since it safely addresses the ammonia release associated with chloramine neutralisation. But I don't use it for wound treatment. I personally believe that the ingredients in 'synthetic slime' can inhibit epithelialisation that is essential in wound reconstruction. My policy for any wounds is keep them warm, keep them clean, feed them well and treat any infection before it spreads.

[stillnzcookie]

are they slightly red around the gills?

Not as far as I can tell. If they were, what could this be a sign of?