harrison, i have 1 400 watt 2 175 watt halides and 2 160 watt vho in a 135 gal and i toss xenia out once a month. My exp is they love light and high alk. Good luck. Joe
SEA,
The plexiglass may melt as the halides get very hot. I think you are supposed to run the halides for 100 hours to burn them in.Always place the coral low in the tank and move it up slowly. Hope this helps. Joe