Here is the outflow tube area at 2-3 BPS. Using a Rena 20 PPI foam filter cut and pressure fitted to tube and casing (jamming it on
). Small bubbles in upper area. Looks to be about 30 small bubbles in the upper filter. Circulated up and down and then the water comes down through the foam with no bubbles at all.
I am pumping with a Eheim 2217 canister which puts out in the mid 300gph. I am pumping an additional 3-4 feet to my tank then if I had a normal setup. I am very happy so far!