Originally Posted by HD Blazingwolf
i cut all my noise by upgrading pipe size.
on my 75, its a 1.5 inch vinyl tube drain with one smooth bend. it also cut co2 usage in half over the 1 inch drain.
wet web media has info on drain sizing for GPH ratings, and the effects on noise.
the overflow kit came with a 1.25" barb for the overflow. I originally had that to an adapter to bring it down to a 1" which is a more common size. i think most of my air issues and noise were caused by this part.
I'm running 2 45 degree angles on both returns to a slip T to turn down 90 and allow air to vent up. once i get under the water I turn another 90 to go parallel with the sump, then a little tubing then another 90 straight up. so this acts as a really nice "trap" and prevents a lot of air from continuing and slows the flow a bit.
it vents nicely and the water coming out doesnt break the water surface in the sump, and bubbling is minimal. I'm still going to put a sponge over the exits there to further disperse any bubbling.
I'll hopefully get the water running this weekend again for final setup/testing. i still need to modify the water purifier thing as a co2 reactor. that will require some dremeling... gotta find that guy and charge it up.