Do you have a sandbed? Do you have a sump w/ return pump, or just the 2 powerheads. Do you skim, what type of skimmer? If you are going to try and keep sps, many, many, many things to consider first to avoid costly casualties. I personally think you are on the low side as far as flow goes. If you have a sandbed, put as much flow as you can, as to not disturb the sandbed. Most people I know push there ph's to the top to maximize indirect flow w/o disruption. I would put in 2 more Hydor 3's if I wanted to keep sps. Try and mount two on the back towards the front glass, and one on each end towards the middle. This should provide enough colliding current to give you nice random/ indirect flow. Flow is very important for happy sps corals...... Good luck....