I bought a new 55 gal aquarium and then stocked it with some zebra danios to help the cycle process. I later bought my Blue JD. Initially he was all over the tank and seemed very active. I've done numerous 20% water changes and all of the fish except my JD seem to be doing really well. My JD stays in hiding most of the time and when he does come out he stays near the bottom with little movement. I've not tested the water but all of the other fish seem fine. The water is clear and looks fine. I also have a couple of Coreys which also seem to be doing well. I'm afraid my JD is not going to make it. Any suggestions would be appreciated.