Ok thanks for the help. Let's see... I'm not sure of the exact temp of the fridge, but it has worked in the past when I had a fungus problem and housed the little guy there. That might be the problem, but I'm kind of doubtful...
As far as the tank goes, it's about a 240 liter tank and I have been working tirelessly to keep the temperature below 20, generally with success. It spiked a day or two where the temp was a little higher, but I brought it back down and still had symptoms a week later. (Floating and curved tail).
I have two external spray-bar type filters to reduce splashing but still filter the water. I live in a basement apartment and have housed the guys here but plan to move them to my school in a couple days where the temperature is a lot more stable due to the constant air-conditioning. I hope that will help. I feed it mostly blood worms, try soft-pelets with limited success, and even used earthworms for a while but they seem a little big and they worked infrequently. I have tried live black worms and they seemed to like those. I have 2 sub-adult about 12 cm axies in the same tank and haven't witnessed any conflict. The were eating a good bit more a few weeks back but both slowed down a good bit recently. I have been using evaporative cooling and thus have to replace water frequently, about 20% weekly. I also try to suck out waste every couple weeks but there really isn't much. I fugure this also manages salinity from the evap cooling so I keep at it. Oh, and I have monitored ammonia consistently and it is good and low. The tank has been cycled for months now. I have been using large gravel for a substrate and am planning on moving to sand when I move the guys to school in a few days. I think the gravel is big enough but am through risking it. I've lost 4 of six juvey axies and am doing all I can... Help!
Thanks again!