When I first filled the tank and ran the sump return pump to test for leaks and to test the sump, the noise from the drain pipe was too loud for our (me and the wife) sanity. Tweaking the ball valve at the drain pipe didn’t help much. It reduced some sound but there was various side effects:
- The water level fluctuated, resulting intermittent draining noises.
- Small bubbles coming out of the bottom of the drain pipe. Not a good thing for maintaining CO2 levels in the water.
- Large pockets of air would be blasted out of the bottom of the drain pipe occasionally, causing lots of splashing and occasional noise.
So I started looking up solutions on the net.