Hey folks. I am looking into building a permanent reef aquarium in my house. My work area is 8' long x 4' tall x 2' Deep. I can go up to 13' if necessary. It will have a 30" base with a sump underneath that will be 6' L x 2' T x 1'8" deep. so what i need some opinions on is a OHF (Over Head Filter) I am thinking that a OHF for a refugium would save space and heat from underneath and i would have more room to grow mangrove saplings. The designs i have in mind would use a pully system to keep the lights at the correct height as they grow. With a small pump just under the water line outside of the internal overflow should be enough for it to send water to the OHF and use a gravity return into the main tank. I want to have some fish in the refugium so it will have a viewing panel. so here is my question. Has anyone used a over head filter on there tank and how were the results?