need help baby discus dying

[JEB]

I have a spawn of blue diamonds about 7. weeks old. I separated them from the parents at about 2 weeks old. They were doing well so I moved them into a larger tank at about 4weeks. They seemed fine and fed aggressively then slowly one would start to die each day. The remainder looked fine. The body of the fish would turn dark behind the gill plates and within a couple of days the fish would slowly start to list and eventually die. The head and gill plates would be normal color but the remainder of the body would turn dark. I did a 3 day treatment of potassium permaganate at 2mg/ liter and a cup of salt each day and they seemed to get better. I then followed up treatment with furan 2 for 12 days. I had minimal losses during the treatment. Now that I have stopped, the losses started again. The losses are still about 1 fish per day a couple of days after the back of the fish turns dark. The breathing is normal and not labored and the gills do not seem affected. I did two treatments with formalin in case of gill flukes but did not seem to have any affect ( one drop per gallon). I also change 50 % of water each day. The temp is 86 F and water is soft at ph 7.4. I do not know what else to do. Maybe give up any treatments and continue water changes? Has anyone experienced anything similar? Nitrites and Ammonia tests are normal. Any help would be appreciated.

[Eddie]

How big is the tank, how many fry total?

[boxters]

fry can not handle such an array of medication. Im not surprised they are dying. The condition of fry very much depends on the condition of the parents during breeding. Anything the parents have is passed on to the fry. As the fry are week with undeveloped imunity, it does not take much to kill them. I suggest treating the parents when they look like spawning. The best thing for fry is lots of clean water and lots of good food

[JEB]

The breeding tank was a 20. The fry totalled about 100 when I moved them into 50. Now there are about 40. The parents were purchased from Hans. When I got them they did not eat for about 6 days. Then they started and looked great. Very hardy eaters. Parents are getting 50% water change per day. They had about 90% hatch rate and corralled the fry right to the sides and were amazing at parenting. If I treat the parents, what would I treat them with as they appear very healthy?

[boxters]

I don't have this problem as I run ozone. I souls treat for flukes and other external parasite and probably pp long bath

[Eddie]

Yeah, I agree that the meds were not required at all. Water quality/changes were the culprit here IMO.

[JEB]

I agree that the change in tanks probably stressed them I have my doubts about water quality being an issue since 100 babies in a 50 gallon tank with 50% water change per day and siphoning off feces twice a day in addition to the large water changes seemed sufficient to me. Anyway, I noticed they get a dark blue blotch in the abdomen first, with a full belly, then spreads to the whole body of the fish without affecting the head or gills. Anyone know what bacteria, protozoa, etc. may cause this?

[Eddie]

I agree that the change in tanks probably stressed them I have my doubts about water quality being an issue since 100 babies in a 50 gallon tank with 50% water change per day and siphoning off feces twice a day in addition to the large water changes seemed sufficient to me. Anyway, I noticed they get a dark blue blotch in the abdomen first, with a full belly, then spreads to the whole body of the fish without affecting the head or gills. Anyone know what bacteria, protozoa, etc. may cause this?


Not sure, fry are easy targets for anything. Symptoms can be similar across the board whether its parasite or bacteria, could be both.