Hey JL, your tank setup is very similar to what I have, you can check out mine and ketchup's tank thread ( Desi and Ketchup tank) in the member tank thread forum whereby I stated in the first msg my exact specifications.
From my original setup, I have amended my lights from the Gisseman now to Ecolamp LED as the heat emitted from the Gisseman ( 2 x 250wat MH & 4 54watt attinics) was killing me... and although now i'm still running my Arctica 1/4, I will be changing to a condensor unit soon for more efficient cooling.
good luck.