Pygmy Cory - Internal bleeding and death - any ideas

[pastie]

Hi,

I've had 2 pygmy cory die of the same thing. They appear to have what looks like massive internal bleeding on their right hand side (see picture), then in less than 24 hours they unfortunatly die.



It first occured when I had finished cycling my tank and added 2 cories to my tank containing 4 white cloud minnows.

The first instance of this occured about 2 days later and I put it doen to new tank syndrome or transportation damage. Since then I've found 3 more pygmies and added them to my more established tank. After about 6 weeks of adding them and 2 months after the original instance the same thing has happened again. The original surviving cory is still alive.

The remaining pygmies seem unaffected.

I was wondering if anyone had any ideas as to what was causing it, or recognised the problem. I don't have any really predatory fish or sharp rocks in the tank which I would think an obvious cause. So I'm a bit confused.

Thanks for your help.


my tank parameters are:

temp - 77f
ph 7.0
soft water
ammonia & nitrate 0
weekly 30% water change

60l Juwel rekord 60 tank with included 280l/h pump, 50w heater, filter & 15 w light

Established 3 months with:
fine gravel substrate,
heavily planted (various plants),

tank mates:

2 sunset platy, 4 whiteclouds, 3 pygmy cory, 4 glowlight tetra, 5 neons.

[corybreed]

Red blotches (hemorrhages)on the body is usually a symptom of a bacterial infection.

Mark

[Coryman]

These blotches can be caused either by a bacterial infection, or more than likely from a sudden nitrate surge or pH crash. The best treatment I have found is Melafix, but you must add an extra air stone. The treatment tends to cause a foaming at the surface which in turn causes a reduction in oxygen absorption. The extra air stone will ensure oxygen levels are maintained.

Ian

[pastie]

Thanks, that might explain it, My Ph has lowered from about 7.5 to about 6.8 since I added plants so that might be the problem. the first one might have died from a difference between the shop and my tank.

[Coryman]

All fish should be introduced into their new environment slowly to avoid shock from condition variances.

Ian