I pretty much do the same as nodima. I do run a powerhead on the same end as output on the opposite side about 6 inches off the bottom to help make a circular flow and it disrupts the debris. When the debris is loose rather than laying, more ends up in my filter and less vacuuming, but sooner cleaning of the filter....nodima said:I try to get a circular flow across the top of the tank, down the far wall and back across the bottom. To do this, the intakes and returns are positioned at the same end of the tank, intakes low, returns pointed across the top of the tank. I find that any debris seems to settle near the intakes, making cleaning easy. However, in heavily scaped tanks, sometimes additional adjustments are needed.