~ janj wrote:
I have a submersible pump feeding an upflow filter. It makes an
annoying noise. The pump itself is silent and the sound of the water
flowing into the pond is pleasant. The problem is the sound of the
water flowing out of the filter. It makes a rushing/gurgling sound. The
water leaves the filter through a closet flange in the side of a
barrel. Can anyone offer a tip on how to silence it? It drowns out the
waterfall. Cam

A bigger opening from filter to waterfall may do the trick. ~ jan
-----------------

The water returns via 1 1/2 inch hose, the waterfall is fed by a
separate pump.

I don't have the ability to increase the size of the opening without
rebuildind the filter and replacing the hose. I tried jamming a piece
of filter material into the opening and the noise disappeared! the
water level in the barrell rose a little but now it all runs
silent.Thanks for the ideas.

Cam