Great post Mike/Mojo, your points about flow [it's not how much it's what you do with it], detritus on rocks, location of detritus piles for siphoning ... dead on from what I've experienced.
I wouldn't have believed it, but I feel like my tank did better
after I removed the large volume closed loop and put in a couple powerheads for better directed flow but half the volume.
I've added more flow since, mainly because when a deal on a 6060 comes by, you take it.
While I hate cords, IMO in a small tall tank like mine the directionality of powerheads is hard to get past without using PVC instead of LR. Different sized/shaped tank ... you may have a different answer to it than I do, or than others here do.
And the aquascaping works into this. I've personally removed rock [and likely will remove one or two more pieces] since having a stable BB tank ... with good results as the flow/detritus->overflow works better.
I sure don't claim to be an expert, just know what I've found being the happy caretaker of my tank in the last 13 months
