I have had my salt water tank set up for about a month and a half. I have plenty of thriving coral. But my two black ice clown fish I have added in about two weeks ago haven't seemed healthy since I got them. I have about 20lbs of Rock but bought it all while it was dry cause I hate hitch hikers. My water parameters have been perfect since I got them. Phosphate 0 nitrate 0 nitrites 0 ph 8.4 salinity .23 ammonia 0 calcium 450 KH 9.5 I don't think I left anything out. Since I've gotten the clowns they kinda just stayed to the bottom of the tank not being active at all. Barely responding to feeding time but they were still eating plenty. They didn't have cloudy eyes or white spots. I woke up the other day to my clean up crew eating the female. I don't know if they killed her or their just doing their job?! 1 peppermint shrimp, three green legged hermit crabs, two emerald crabs, and a few turbos. The only thing I added in since I get the fish was a couple different corals and some chaeto. Then two days later a couple snails have died and two hermits as well. The tank is a 40g all in one fusion. The chaeto is in the back with phosogaurd, carbon, and a decent skimmer. The tank has decent flow and I've done atleast 15 gallon water changes every week scrubbed the glass and filtered the sand bed. I thought maybe too much cleaning and killing the good bacteria but I don't know. Also I thought maybe a few ph spikes because I dosed my water change water with kalkwasser a day before doing the water change and then dumped it in which resulted in some kalkwasser residue in the display. I won't do that anymore I know that. Any thoughts? Should I do anything to try to help my other clown ? I've been in the hobby for over a year with much success but I don't know? Could there have been something in the chaeto?