Sick C. atropersonatus

corydorus · Post by **corydorus** » 28 Jul 2005, 04:08

This fellow has been with me for more than 2 years.
From a thin and weak fellow to a strong one.

At one time (maybe a year ago) almost his entire tail gone. But he recovered. But his tail is always at slightly burn-our fray condition. I thought is natural.

Recently the problem comes back again except is more serious. It reaches the caudal area as photo attached.
The taiwan shrimps are horrible, they keep tryin to feed on his tail live as the rotting fin attracts them which adds more injury.

He was gone the next day. and he is the only one who got this out of 20 different corys in the tank.

The water condition.
ph: 6.5
Kh: 3.0
Nitrite / Ammonia : 0

Who are the culprits ?

Can it be possible the addition of minutes amount of SALTs introduced by bbs feeding can be a problem ?

corydorus · Post by **corydorus** » 17 Aug 2005, 07:26

someone says is probably old age ....

MatsP · Post by **MatsP** » 17 Aug 2005, 09:08

I find it unlikely to be old age. Unless the fish was OLD when you got it, it's most likely got another ten or more years to live. Cory's are much longer lived than for instance guppies or danios, and even they live for a few years in captivity when looked after correctly.

It may be that this particular fish has some sort of immune system deficiency, so it can't fight infections as well as the others in the tank... If you have more of the same specie, and they are happily living in the same tank, I don't think that it's something in the tank that causes the problem.

Salt from brine-shrimps... Let's do some math: Brine shrimps are bred in something like 3% salt. You add maybe a tablespoon of water (15 ml = 15g) per feeding. Let's say your tank is 50L, and 30% water change per week. 15g * 3% = 0.45g salt per feeding. Two feedings per day => 0.9g salt per day -> 6.3g salt per week. Keep 70% of that (30% goes away with the water change each week). 6.3 * 0.7 * 52 = 229.3g salt per year. 229 / 50000 => 0.4% salt.

So, maybe, if you're feeding a tablespoon's worth of brineshrimp twice a day, you'd get some salt worth noting. But I doubt that's what your problem is.

--
Mats

Starsky · Post by **Starsky** » 17 Aug 2005, 17:36

Looks like finrot. It's very rare among corys because of their "armor" among other things. This makes them more resistant to external bacteria than other fish. Maybe that's why the other corys in the tank did not get infected. But since this particular fish already got infected before, maybe his resistance wasn't as good as the rest anymore.
Two of my bettas get finrot once in a while for heaven knows what reasons. They recover after the salt baths and methylene blue treatments. But then they get finrot again. I don't have problems with my other bettas though. weird.

Sorry about your little guy. I lost one of my schwartziis the other day, too. He didn't look good when i got him. He's got cloudy eyes but he was active and feeding well so i thought he'd get better. After a few weeks I saw him on his side under the sponge filter with torn fins, barely alive. I put him in quarantine with medication but he died the next day.

DeepFriedIctalurus · Post by **DeepFriedIctalurus** » 17 Aug 2005, 23:35

How much time passed between when you first noticed it came back, and the poor fairy cat passed away?

Every once in a while I see bacterial infection in shops around here (even those taking good care of seperated tanks) that spreads across the body very quickly, and no particular types of smaller fish seem to be susceptible. What's unusual about this infection is regardless of it's necrotizing ability, it's not very contagious & seems to show up only sporadicly on individual fish.

corydorus · Post by **corydorus** » 18 Aug 2005, 03:09

The rots that kills him last about a week. Start noticing the shrimps keep get attracted to his tail fin though he is swimming and eating ok. He will just ignore them and swim a small distance away.

But his tails soon get shorter and shorter with difficult in swimming till he die the day after the pictures are taken. Btw he is stil taking food quite actively till the day I isolate him.

The betta story seems very similar to mine. thanks for sharing.

Anyway to play safe, i have practised filtering out the salt water before feeding.

I still miss the strong rugged textured leopard spotted white skin that he has grown into after two years in captivity. It looks read cool in actual.

Starsky · Post by **Starsky** » 18 Aug 2005, 16:42

It's not hard to see how you'd miss your fairy cat-- he looked very beautiful. Ever since i saw your pictures of them, i wanted to get some myself. But it's very hard to find corys in my area.

DeepFriedIctalurus · Post by **DeepFriedIctalurus** » 19 Aug 2005, 01:14

corydorus wrote:The rots that kills him last about a week.

It must be another infection then, the one I'm referring to can kill a fish in a single day from the time it's 1st noticed. I really shouldn't have bothered to mention it anyway, since the appearance of your fish was a bit different from what I've seen.

Pics of this "super bacteria" will be posted on the forums here as soon as I get another opportunity to take some!