good quality check valve
I have my skimmer with a 3000 gph pump in it out to the waterfall. I have a cheap check valve installed directly off the pump mounted vertically.
My problem is that the check valves do not do the job after a while. my waterfall tank empties back into the skimmer when I clean the skimmer.
any advise on a good brand of check valve. I use 2" pvc, the pump has a 1 1/2 inch outlet.