18 ninches and i know its to much light cause they open up more the farther away i put them from the lights.i've been raising the lights some.
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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 |