Suppose you have one pump for pool/spa circulation and a separate pump for spa jets.

The circ pump pumps through the filter, heater, and salt water chlorine generator. The jet pump does not.

Do the circ pump and jet pump both pump back through the same returns/inlets/jets in the spa? I wouldn't think so, but I can't find any design information to confirm or deny.

If the answer is yes, what happens if I want to operate the spa (with jets) while the system is performing its normally scheduled circulation of the spa water?

I would think that the discharge of the circ pump would be plumbed to a single return in the spa and that the discharge of the jet pump would be plumbed to "X" jets in the spa. The two circuits would not cross over at all.

Your help would be very much appreciated.