This is a great reason to have a pressure gauge on the line going to the pond. Or the manifold where the lines go to the pond. You can check to see if the pressure is different. Another way to check is to plug the line with your finger while looking at the gauge. If it can't build more than a few PSI then the diaphragm is bad too. OR it could be a bearing going bad.

www.hoosierpondpros.com


http://www.pondboss.com/subscribe.asp?c=4
3/4 to 1 1/4 ac pond LMB, SMB, PS, BG, RES, CC, YP, Bardello BG, (RBT & Blue Tilapia - seasonal).