help #hammer coral

HI, im fairly new to the hobby. I have a reef tank just over 8 months old. Ive never tested my reef tank and have always hoped for the best until now. I have alot of corals that have died (Zoa/ Goni / Hammer/ Frogspawn / Favia / Acro / candy cane and even GSP) everything looked well when i...

All my other coral and fish are doing fine but my hammer coral just slowly started Shrinking for some reason. All my params have been the exact same and he’s been in the same spot for about a month. It was plump and growing quickly and now this..