My Clarkii is acting very strangely ever since I took the 2 blue/green chromis out of his tank. It is now just him, a feather duster, a orange starfish, and a scallop in the 20 gallon tank. There is also a couple pounds of live rock. Ammonia is 0, Ites are .5, ates are at 40, and the salinity and temp are fine. Could the ates be whats causing all this trouble? I did a water change yesterday and that didn't seem to do much. Please help and let me know if there is anymore info I need to give you. Thanks