I can't speak about the electric diaphragm pump but once I went with my air diaphragm pump I decided I would never go back to a gear pump. The compressor I use is just an average size pancake style pump. My only complaint was listening to the compressor, so when I ran power from my sugarhouse to my new shop 125' away, I buried an air line (just 1" black poly rated at 200 psi), now i like the diaphragm pump even more, the little compressor is in the shop and it's much quieter in the sugarhouse. I find it desirable to regulate the pump speed by either opening or closing the air valve I put on the air supply line right at the diaphragm pump, or turning the air pressure up or down, also right at the pump while my compressor is running up to 135 PSI, I usually have the inlet air at 40-50 PSI. It's all about control.
Dave Klish, I recently ordered a 2x6 wood fired evaporator from A&A Sheet Metal which I will be converting to oil fired
Now have solar, 2x6 finish pan, 5 bank 7x7 filter press, large water jacketed bottler, and tankless water heater.
Recently bought another Gingerich RO, this one was a 125, but a second membrane was added thus is a 250, like I had.
After running a 2x3, a 2x6, 3x8 tapping from 79 taps up to 1320 all woodfired, now I'm going to a 2x6 oil fired and a 200-425 taps.