[prow]

my tank is 72"L x18"W x20"depth anyone have an idea of light config. also i have a standard canopy that is olny like 4" over the water line any tips on raising it so i can use both pc and metal halide but maintain both at the right hight above the water line. my big question is what watt and k's bulbs should i use and how many of each. this tank will be for mixed corals, clams, bubble perl, mushrooms, ect.ect...

[Reefland]

Hi prow, Welcome to Reefland!

I know I typed up a reply to your inquiry today at work, I must have not hit the submit button or something? Anyways...

Are you planning on trying to fit MH and PC's in your existing hood or are you prepared to do something completely different?

3-250w metal halides would be the best fit for your size tank. Halides with a decent reflector can cover a 2'x2' area so for completel coverage you'll need 3. Now some people that also utilize some full spetrum VHO or PC's the entire length of their tank will opt for just 2 halides over a 6' tank. They do however live with darker ends of the tank but some enjoy this so they have some shaded areas for less light requiring corals.

The color temperature of the bulb you use is up to you. If your in it for PAR, the 6500k bulbs are the best producers but most people find they have to supplement them heavily with actinics so the tank is pleasing to their eye. People that don't use actinics might choose 20k lights although they do not produce the PAR that other bulbs do. People looking for the best of both worlds go with 10k's...it's really up to what you want to get out of your system.