The 1 cfm is the standard amount of air volume to get the disk to perform "normally". They will accept more or less air volume but then the efficiency becomes less due to larger or fewer bubbles produced.
Depending on the type of compressor, the PSI produced to the diffuser will, at a minimum, normally only be 1/2 the depth. Most standard aeration compressors will generate only what PSI that is needed to operate the system based on water depth, type of diffuser, airline restrictions etc. So higher PSI than 1/2 the depth means there are restrictions in the aeration system that require more PSI to get air out of the diffuser/s. The air gauge will measure the maximum PSI needed to run the deepest diffuser. All shallower diffusers will operate at less PSI than the deepest diffuser. As the PSI increases the air flow rate (CFM) almost always decreases.

What are you using to generate your air flow?

Last edited by Bill Cody; 03/10/17 03:34 PM.
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