I have this same boat that I purchased a couple months ago. The Pro-Air switch is just as you said. It wil provide fresh oxygen to the Live-well to help keep the fish alive

2. Master Aerator will pump water into the livewell from the lake. It does not recirculate the water. Just fills live wells.

3. Recirc pump is the pumps that will recirc your water. I am not sure if yours does, but mine also has a pump out. This will also pump out the water from the live well if you have this feature. I hope this helps. Let me know if you need anything further.

You can also control these pumps from the bow of the boat.