I tried adding the 2 scrubbers and it didn't really help. The small microbubbles get sucked right through.
Even when I turn the flow down low enough that the large bubbles only make it a few inches down the housing, the microbubbles still make it all the way to the bottom. I'm surprised I'm having this problem with the 20" housing. I must have been getting down to 200gph or so.
Any other suggestions? I'm about to give up and use a separate small pump to drive the reactor, which is disappointing since I would never have built a 20" Cerges if I knew was going to have to run a separate pump for it anyway.