Dick I have the Gast pump placed in my work shed ( thin walls ) and have the garden hose through the wall. When walking by you can almost not even hear it. It would take you a bit to listen for it. This was one of my larger concerns. I did not want a system that was loud and produced alot of noise with the pump or with the Diffuser. The nice thing with both of these is that it is so quiet that nature is not disturbed and if you did not know it was there or did not see the bubbles you would never guess it was there.
I placed the diffuser in an old 5 gallon bucket and have a rope attached to it that is tied to a floating log that a painted turtle has adopted for sunning and the fatheads are using for spawning. The fat heads also use the rope to eat algea and other nutrients off from as it comes up from the bottom. Its sort of fun to watch them as well as they stay around it as the bubbles are moving the water.
I am getting about 1.5 SCFM of air and the water is moving nicely around the pond. My biggest worry was that I had to cut back the amount of time that the unit was on because I was losing my bloom and the minnows were hungry.
Along with what was posted I added a smalle $6 timer from Homedepot. It has been working great and I have the unit set to go on and off about 3 times a day thus far. The water is clean clear and sweet smelling and have happy fish.
That being said, good luck and have fun!!
