Troubleshooting:

Complete system: 0523 Gast rotary vane, 180' +/- 1/2" i.d. weighted hose, single Vertex co-active shallow water air station(installed as received i.e. no valves installed).

System installed at 7' - 9psi
Air station on shore - 7psi
Air station on shore both diffuser heads removed - 3.5psi
Air station disconnected from airline - 3.5psi

I had a couple old MD3 style diffusers:

Air station on shore w/1 vertex shallow water diffuser and 1 Ecologix 250D (MD3) style diffuser installed - 4psi
System re-installed at 7' with above diffuser head combination - 6.5psi

It is now bubbling away at 6.5psi with the "mis-matched" diffuser head combination.

Sooooo. What do you guys think that tells us?

Rotary pump 0523 with X number of feet of hose beyond 2' (as tested by Ted) and the Vertex shallow water diffusers causes too much back pressure? That's my theory....?

Any installed systems similar to mine and no problem? Longer hose runs? Rocking piston or ? style pumps work better than a rotary vane with the Vertex shallow water diffusers? The inlet orifice on the Vertex diffuser is definitely much smaller than the orifice on the MD3 style diffuser. I guess that would explain my pressure drop using the MD3 diffuser head.

1/2" i.d. hose not optimal for the length of my run?

Thanks for both of you guys commenting and look forward to the next round!!

Chuck

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