I'd check voltage. IIRC your electric lines going to the compressor are marginal for voltage drop (sized on the small side).

The vertex system that I installed a month ago is running 3 pairs of duffusers thru roughly 375 feet of air line in 7, 5 and 4 foot water depths and it showed 0 back pressure on the system.

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3/4 to 1 1/4 ac pond LMB, SMB, PS, BG, RES, CC, YP, Bardello BG, (RBT & Blue Tilapia - seasonal).