Hang on here, I'm starting to loose the plot.

To recap from your diagram you have the fengda compressor I listed previously? This says it has a small 0.3l tank with a pressure valve that you have set to 50psi. Connected to this is another pressure valve set to 25psi, and this is connected to your AB ?

So you are spraying at 25psi ?

Have I got that right so far ?

Pantherman