I picked up 2 of these bad boys from altex they push 110 CFM and there not very loud http://www.altex.com/product_info.ph...oducts_id=3730
I have a 5' tank so i put one on each side blowing in and my back is cut out so that helps alot Oh yea my lighting is 2-250w mh and 3 5' VHO superactinic