I've seen some people mention that circulation alone is enough to aerate the water: I'm just wondering at what point can I get away with no air pumps? If I have a 300l RDWC system and a 4000 lph pump circulating the water that makes the water do a complete rotation 13.3 times an hour or every 4.5 minutes. The air bubbles popping in my system are causing way to much noise in the rooms below so I'm trying to design a system that can work without the air pump. The water does splash into the control bucket causing a lot of aeration too if that helps. I currently only have a rotation every 30 minutes as I didn't make the connecting pipe between buckets large enough. I'm gonna upgrade them to 2 inch pipe and the pump to 4000 lph if that's enough for aeration Anyone got any experience with doing this?