There's a problem in my tank which is killing all my corys, and after months of searching here and there I can't work what is wrong.
Up to a couple of months ago I had 7 corys in the 39g community tank - 4 peppered and 3 bronze. They've been happy and healthy for the couple of years, mating all the time and supposedly enjoying their home. Then several weeks ago I noticed the biggest peppered female had a small wound on her head between the eyes. It looked like she had run into something and gouged a hole in the flesh.
So I started treating the tank with melafix to try and help the wound heal. It didn't help. Over the next couple of weeks the wound got bigger, she stopped eating, become lethargic and in a few days was dead. Not long after that another of the peppered corys come down with the same thing - a hole in the flesh between the eyes. Thinking they may be injuring themselves on some wood in the tank I removed all the wood and decore. But treating with melafix and doing large water changes once again didn't help. Within a couple of weeks that one was dead too.
Well, I'm now down to one peppered and 2 bronze cory's - and I noticed yesterday the smallest bronze has this GITH (Gouge In The Head) disease as well. The wound has doubled in size in 24 hours. To me, it seems like some sort of flesh eating disease or something. The fish don't seem to act sick or go off their food until the wound pretty much bridges the entire area between the eyes. There doesn't seem to be any other symptoms - no blotches/sores in other areas or anything else.
Tank parameters have been stable, no nitrite/ammonia spikes that I know of, plants are growing and the bristlenoses, kuhlis and snails seem unaffected by this. So does anyone know what could be causing this? The only things I've come up with is either hexamita (doubt it) or fish TB. Any other ideas?
BTW, I've now QT'd the survivors, but it doesn't seem to be helping.
Up to a couple of months ago I had 7 corys in the 39g community tank - 4 peppered and 3 bronze. They've been happy and healthy for the couple of years, mating all the time and supposedly enjoying their home. Then several weeks ago I noticed the biggest peppered female had a small wound on her head between the eyes. It looked like she had run into something and gouged a hole in the flesh.
So I started treating the tank with melafix to try and help the wound heal. It didn't help. Over the next couple of weeks the wound got bigger, she stopped eating, become lethargic and in a few days was dead. Not long after that another of the peppered corys come down with the same thing - a hole in the flesh between the eyes. Thinking they may be injuring themselves on some wood in the tank I removed all the wood and decore. But treating with melafix and doing large water changes once again didn't help. Within a couple of weeks that one was dead too.
Well, I'm now down to one peppered and 2 bronze cory's - and I noticed yesterday the smallest bronze has this GITH (Gouge In The Head) disease as well. The wound has doubled in size in 24 hours. To me, it seems like some sort of flesh eating disease or something. The fish don't seem to act sick or go off their food until the wound pretty much bridges the entire area between the eyes. There doesn't seem to be any other symptoms - no blotches/sores in other areas or anything else.
Tank parameters have been stable, no nitrite/ammonia spikes that I know of, plants are growing and the bristlenoses, kuhlis and snails seem unaffected by this. So does anyone know what could be causing this? The only things I've come up with is either hexamita (doubt it) or fish TB. Any other ideas?
BTW, I've now QT'd the survivors, but it doesn't seem to be helping.