So when my tank finished cylcing yesterday I immediatly went out to get some fish. It took almost 5 weeks to get the nitrites to 0 and ammonia < .25 ppm. After about a 25% water change i checked my nitrates and was suprised to see it at 0. I went and grabbed a pair of Brichardi for the tank. After a couple of hours I noticed a white "thing" forming on thier eyes, and they seemed to be acting lethargic ,either hanging out on the bottom of the tank or at the top. I kept the lights off for the day and then into the night. I woke up around 6 and they were both still alive but still acting pretty lazy and still with the white things on thier eyes. About 2 hours later I checked on them again and found them both dead when i took them out of the tank i noticed alot of deterioration on the fins and maybe a little bit of white growth on the edges although this could have just been the colors of their fins. Checked the water again 0 nitrates and close to 0 ammonia. When I cycled the tank I lost 4 out of 5 Dainos that showed the same symptoms but I just figured it was because of the nitrite spike. Anyone have any ideas as to what this could be? I'm clueless as I have never had any problems with my tanks this quickly. Any help would be appreciated ...Thanks