sometimes they just die off by themselves,you will get so many different answers.i used kalkwasser to cover them up.it does'nt poison them like it does to aiptasia but it will smother some of them.i hear joes juice kills them but never tried it.for no reasom mine is getting smaller,something must be eatting them but i have no clue.i have seen stomatella snails neer it and an emerald crab but i've been told they would'nt eat it.
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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 | 
Hydrozoan'a 
