In one of my tanks, I use a sponge filter driven by an air pump. The pump was cheap and is pretty loud. Does anyone have reccommendations on a more quiet pump? Thanks!
The Rena or Tetra DeepWater pumps are the quitest. Only problem is that the Renas dont give you as much power, so buy one 1 size bigger than you need. The Tetras give you lots of air but are a bit loader.
Diehard Rena fan here, ultra quiet, ultra reliable air pumps!
My emergancy battery powered air pumps are Penn Plax B10 -n- B11, not as noisy as some regular air pumps.
Tricks to quiet your air pumps;
Put them on a folded paper towel or washcloth.
Buy the stick on felt feet for'em.
Don't place'em on a surface that resonates sound easily.
I've found the Hagen Elite/Optima series to be the quietest of the 1/2 dozen or so different brands of pumps that I've tried myself. Both of my Tetratec Deepwater pumps were roaring monsters that broke down (torn diaphragm) in under two years use...I wouldn't recommend them.
I only use airpumps to power my brineshrimp hatchery, though. To cut down the noise, I made a plexiglass platform that rests on a sponge. They're quieter than the floor fan in the same room, which is good enough for me.