i need things super quiet here so i bit the bullet and purchased some 1" thick america mat after finding their aquarium pump page through google. SOUNDPROOFING YOUR AQUARIUM PUMP MOTOR America Mat Closed cell foam i have a loud aquarium pump (Tetra Whisper 60) mixing my nutrients and made a little little housing out of this mat. i made it with a rounded top, like a mailbox. it made a big differene but i need to recreate teh box and it should nearly eliminate the noise. I left too larege of breether holes in it so it is a bit loud. thaty plus i think putting the whole thing inside of another box would help as well. when the temp drops here a bit, i am going to go back up int he attick and build a box around the vortex 6" fan out of 3/4" mdf and line it with the america mat and then will report back to this thread. currently, the vortex is up in insulated attic and i wrapped it with several bats of insulation. additionally, i swapped out the uninsulated tubing for insulated tubing up in the attic. this actually helped a lot but not enough. there is a thread on one of these boards where a guy did a similar thing to what i ma doing here but was using an even more expensive material that weighed a ton (like ~100 pounds?). i will also line the back of the closet door and see how much that helps. i am picky ablut the noise and need things super quiet. sorry for the lack of pics. will try to come back later and add them