My hammer coral, frogspawn and scolys are all receding and dying. Running gfo and protein skimmer, no angels for nipping. Levels are normal 1.025, phosphates low and nitrates low. Alk steady around 8.4-8.6. I’m going nuts losing all this coral. Only new addition is a peppermint shrimp, could he be destroying all these corals???? PleSe help me