I think many people get all to confused with the term flow or turn over rates .. The best or average turn over rate is 4 to 5 times tops thats the amount of the aquarium that actually passes through the sump and past the skimmer So for a 75 gal about 300 to 350 GPH through the sump.. Now with the internal recirculating rates 10 to 20x's is fine .. This is averaged by the amount of GPH the recirculating pump or pumps if powerhead or such devices are used . If you are dealing with SPS corals then as long as it is not blasted by the direct strong flows of circulation water then you can not really have to much. Not nay Reef ready 75 I ever saw would flow 750GPH anyways through the 1 inch bulkhead.. _________ Some of the world's greatest feats were accomplished by people not smart enough to know they were impossible (Doug Larson) |