Thanks Ted,

I took a better look at the pump and the blue manifold. The pump is a Stratus Piston Compressor ERP25 like you mentioned. Like this one... http://www.underwaterwarehouse.com/Strat...sor-p-1537.html

It does show it's a 3.5. As far as the blue manifold goes, there is a threaded end at the end of it. What kind of store locally would have a 90 degree elbow to fit it. Home Depot?

If I understand your earlier post, remove the relief valve from the center and put it on the 90 degree elbow. Then put another valve in between my two hoses. In normal circumstances, would I leave that valve wide open, partially open, etc? I understand if it's too noisy, to get a section of air hose and run it to the pond to help reduce the noise.

It seems the easiest way to go for me (that I can handle on my own) is find the elbow and a valve. That is if in fact the pump is too much for my two diffusers in the size pond I have.