Valterra200-C20W PVC Swing (No Spring) Check Valve, Clear Blue, 2" Slip, White

We have three pumps installed in parallel now, a solar pump, a older variable speed to save AC power, and a bronto pump for hi flow needs. On the inlet side, these valves automatically prevent flow back through the inactive pumps without turning handles. On the outlet side, these prevent over pressure or leaks into the inactive pumps when opening baskets for cleaning. Note that you should use manual gate valves when removing pumps.

Don’t close completely the water pass

I needed it for my pond so I could see if any of the turtle shells were plugging it up. I had to cut up a pitcher to put over the valve so the moss wouldn't grow so fast & block my sight. The hard part was finding a brush that would clean it out when it did become to thick. All & all it really works great; I first had a spring loaded one but it wouldn't open all the way & would eventually would plug up.

Failed after a few months use

I was getting filter material (and dirt) backwashing into my pool when the pump would shut down. Cut out a section of pipe before the filter and installed this valve. No more backflow problem. A cheap and easy solution!