Reducing pump/water noise

Not sure if it would apply, in my situation I had a tank with a pump output above water (splashing constantly) so I laid a piece of plastic over eggcrate with a screen on it half the tank and put a folded towel on that, reduced it by 90% /shrug.. sucked because the towel would get damp every few weeks, but much nicer than the noise

 

A clean rubber mat under the base of the pump helps alot with pump noise...maybe adding a few angles in your plumbing work will stop some of the swooshing sound by slowing the flow of water enough to keep the pipes fuller and under more pressure...or a ball valve somewhere in your plumbing. I don't have any plumbing running from my tank to the basement but i do have everything in my stand as far as plumbing goes and i incorporated ball valves and 45 degree angles in the pipes in few places and the only noise i hear is the water that falls about 6 inches into my sump...which is a soothing sound to me...but my my pump and return plumbing is very quiet.

 

Do you have any soft tubing coming off of the pump? Hard PVC will transfer vibrations and sound very well and if you have the PVC pipe clamped or hung from your floor joists it will transfer and amplify the sound as well. A couple feet of soft tubing on the intake and output of the pump will dampen the vibrations a lot for you.

 

I asked a friend who is a plumber...he is more familiar with residential plumbing as opposed to aquarium style hobby plumbing but he suggested possibly adding more plumbing straps closer together. He also said a thick foam pipe indulation should help as well. He said to go over your existing plumbing straps and make sure the are tight to you floor joists etc. and to make sure your new straps are tight as well. He said to use straps at 3-4 foot intervals.as for pipe insulation he said foam is better at noise reduction then fiberglass pipe insulators.

 

A fernco fitting on both sides of the pump should help a lot. We use them on almost all of the pumps at central campus to cut down on vibration.