Joey and Sue,see hows this fit, Vertex Air 1 Mini with additional (2nd) diffuser (Air2 Mini), 2.5 cfm total which would allow for a minimum of 1 cfm per station and the ability to turn more and (different) gallons than any single diffuser.The lift on one Flex Air would be approx 1/4 that of two discs working side by side or "CoActive" thus taking advantage of the "synergism"Sorry about getting brand specific but is the only 2.5 cfm piston pump that I know of,Rotary vanes do well when starting with 4.2 cfm open flow,which may be a lot of cfm for your situation Ted
