Air Check Valves???

I just purchased a pondmaster AP-60 air pump and installed it yesterday. Did narrow it down to only flowing through 2 air lines and I put check valves in the lines like I have always done with smaller pumps and it makes this loud high pitch squealing noise as the air travels through the check valve.

Do you all use check valves when you use these bigger pumps? if so what ones? Is there bigger check valves? I believe what is causing it is that it is just too much air flowing through those tiny check valves and it makes the little rubber mouth in the check valve squeal as the air goes over it.

DB junkie said:

NO check valves here.

My pump is up by the floor joists - hooked to PVC with valves in it. The PVC is hanging from the joists.

Second one is also tied to PVC that is above all the tanks.

I bet that pump is flat out pissed about being reduced that much.

Click to expand...

It is definitely moving a lot of air through the 2 stones. I have them running 2 DIY K1 filters inside the tank just for the next few weeks first to start some of the K1 getting cycled until I can build the sump and secondly because I don't feel comfortable building my first sump right before I am going to be out of town for a week. So I will spread it out a little better once I build the sump. But since this is my first time with a pump of this size. Is it bad to have it necked down this much? Will it hurt anything?