I use a PH monitor. Honestly I can't remember what effluent rate I'm running, but the BPM is about 60 and the PH is 6.8 ou tof the 2nd chamber. Start way under and work your way up....different systems have different loads. I have a derasa clam which is laying down shell at 1/3rd inch a month, 2 maximas and a dozen or 2 frags all growing well, so I have a VERY high demand! Yes, I do use the solenoid that came with my regulator, but don't use a dosing pump to feed...just a maxijet pump.