I think I read that each Vertex disk is rated at 1 cfm each. Or is that per "station" which has two disks each? So the tubing would use about .5 cfm per 10 feet of tubing? The Vertex system was their 3/4 hp system, designed for four air stations. With just the use of three stations, there should be a one station (two disk) reserve capacity. That would mean up to 2 cfm in reserve? If reading correctly about 40 to 50 feet of bubble tubing. Does that seem correct?

How has the bubble tubing worked for folks? Anyone care to relate their experience with the tubing? If performance wasn't great, my next option would be looking at tubular membrane diffusers or alumina air stones. But I think the tubular membrane diffusers may have more surface area than the disk diffusers and may use too much air from the system. As you mentioned, that could be counter productive. I don't want to do that.