Hi eveyone.Mike here.I was referred to this site by someone at fish town usa in queens.Well I've been doing this salt water thing for about a year now I'am currently runing a 55 gallon reef with Tek T5 ho light a aquamedic multi skimmer and a 30 gallon reugium.lately I notice that the tips of some of my acropora turning a brownish color is there any reason for this.