Thanks for the suggestions. I've been doing weekly water tests and everything is stable. pH 8.1, nitrates 0, nitrites 0, ammonia 0, PO4 0, Ca 400, KA 6 (I'm trying to raise this slowly) Temp 79°, salinity 1.025. The Firefish went missing the day that my Orange Spot Goby jumped out of the tank. I...