Right now i have 260 watts of power compact. In a week or so im getting a MH retrofit. I could do a Crocea after i upgrade. (NOTE: no clams will be added for several months and until i have MH lighting). A couple questions: Should I go with a 175 or 250 watt MH. And since this tank is made up entirely of the water, rock, sand...etc. i used in my old system, how long do i have to wait until this tank is considered mature? The 90 gallon was 11 months old when i made the switch. Thanks!