how high should i keep my light fixture above the water level? I am lighting a 24 inch deep tank with 2X250 DE halides with 2X54 T5 blues. keeping a reef tank from softies to lps to sps. is 8 inches too high?
8 inches should be fine. If you can get 12 inches start there but 8 is ok as long as you have a shield for the bulbs for water splash. I assume you have a fixture with lenses in place. if so you can go down to 6 or even 4 inches. so start up higher and lower if you need more intensity. good luck pics as you can.