Continuing the conversation for Piper here to remove it from the sponsor's forum. Charlie, To give you some perspective, I have a MP40 and a Coralife 5800 system on my 150 gallon tank. It's a LOT of flow and I've had to control the flow so I don't get sand storm. http://reefbuilders.com/2011/08/01/coralife-dc-wavemaker-pumps/ http://www.coralifeproducts.com/Files/Product/wavemaker-instructions.pdf The Coralife's are pretty cool. Independent controller with a "night sensor". It works well. Only thing I don't like about it is the lack of magnet mounts. It uses suction cups that can fall off. Instead, I used Koralia wet/dry side magnets to attach them. The 5800 is LOTS of flow, but you could get the 2600 system instead of a MP40 (if you're on a budget). MP40 does 3000GPH. Just a thought.