don't panic yet.it will only hurt corals and not always.it will likely pass,be patient.when your tank is stable add your hermits and snails to eat it,and fish ,keep up on maintenance.it will eventually lose the battle,then you can add coral.
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55 gallon reef with 4x54 watt t5,29 gallon sump,red monti cap,1blue echinophyllia,trumpet,red lobo,2 toadstools 1purple and 1neon,gsp,xenia and yellow xenia,red ,many mushrooms,2 giant frilly shrooms,cabbage coral,yellow polyps,many zoos,1 orange and one neon green nepthia,duncans,cladiella | 
liv rock regular alagee 
