<a href=showthread.php?s=&postid=14927007#post14927007 target=_blank>Originally posted</a> by sacremon
I tried a pair of Mag7 pumps initially, one on each return, and got a fair amount of microbubbles. I eventually chalked that up to cavitation - the pumps were supplying too much flow. I've replaced them with Mag5 and that is doing much better.