I am a strong believer in ciculation as an essential element in marine aquaria. In the wild sea creatures are subject to constant chaotic flow and with all the elements added together I have a water movement of over 16000 litres an hour!
I believe strong circulation is essential to maintaining good water quality, strong currents greatly assist in the breaking down of organic waste for removal by the skimmer. Anemones, mussels, clams and barnacles need good water flow to feed successfully. I have noticed that nitrate levels in all marine aquaria stay lower with better circulation.