So this mean you use the power heads instead of a spray bar for this work? Interesting! I will think of this because my tank is lack of water movement. LOL
Yes, I don't use a spray bar, but the eheim 2215 outflow is still the biggest water mover in the tank. The koralias help prevent any dead zones. Their only drawback is that they can be dangerous to shrimp due to their open design. I no longer keep shrimp in this tank.