What is the flow rate for each jet(gpm)? This is necessary to know so you can properly size the pump and piping. Then you can deal with the venturis or air injector.

After you figure out what gpm each jet makes then you need to figure out what line sizes you need to have to be within even the minimum code compliance. For example if you took a standard Pentair 5hp pump that produces 260gpm you would need a 5" suction and a 4" return just to meet the minimum code feet per second of water requirement for suction and discharge outlets. 2" and 1.5" pipes are to small even if you only ran 5 jets.

Well, I had a plumber that didn't know what he was doing when he installed the pipes. He actually wanted to run all 16 jets off the 2" pipe. Luckily there is a 1 1/2" pipe that I can use too. The jets are small, I think 10gpm. I plan on running the 3 drains with 2" pipe into a 4" pipe to pump then the 2" return will run 10 jets & the 1 1/2" will run 6 jets. Will this work ok? Unfortunately I cannot change pipe sizes any more....they are all in concrete already.

Then the question about the air supply, which way I should go.

This post was edited by trisr on Fri, Jul 18, 14 at 12:12

What code compliance are you referring to by the way? I live in Panama, Central America.

I'm talking about codes set forth by the ANSPI which says that suction lines should not exceed 6.5 feet per second of water and 8.0 feet per second on the return side. These are minimum codes! You should always try for less than that.
I'm sure those codes don't apply in Panama but they are good to follow.

Could someone possibly help me with my original question about the air supply for the stacked micro jets? Thanks!

Please tell me how this worked out, this a very simple issue pre gunite but this can get handled