Eyes Gone

[paulthegreat]

I had one of my juvie swords die earlier in the week and thought it was from getting stuck behind the pump. I noted that one of the eyes was gone and assumed that it had been nibbled at by the yoyo loaches. Last night I moved the 101 new fry to the growout but left them in the trap to observe for a few days so I could remove the weak and deformed. I found two that had eye problems. One had an eye missing and the other had an eye that looked damaged, kinda like it had a "black eye". I then discovered one of my juvenile swords hiding out it the java fern of the main tank and realised that one of the eyes was missing. My water quality is good 0 ammonia 0 nitrite but the nitrate had gotten up to about 50mg/L. I had postponed doing the weekly partial change waiting on the Mommy Sword to birth. I did a 50 % change on the main tank and a 20% on the growout last night. All affected fish have been disposed of. Any ideas on what could have caused this?

 

[Toadfish]

Ya that one's tough, one of the possibilities could be genetics. Because the way I understand it these fry have been seperated from the other fish so that likely rules out damage. Often when you buy fish from the same tank they are probably siblings, and their parents may have been siblings, and their parents befaore them. And eventually you get problems as you can only breed siblings of siblings for 3-4 generations before you get birth defects or weaknesses. I f you are interested in breeding them I would recommend you find another batch of swords (ie not related to your current swords) and mix up you school. Now it could be something else like an infection of sorts and is targeting the weak fish. But that is difficult to diagnose unless there are other symptoms.