The project that Im working on. I am aerating a pond with an air stone diffuser. The diffuser requires 2 CFM of air flow to work optimally. Im feeding this diffuser with 1/2" pvc line at a distance from compressor to stone is approx. 200 feet. The stone is placed 10 feet deep under the water. At what psi would in need to set my regulator to maintain an even volume of 2 CFM to my diffuser. This will help me size my compressor which is what im trying to do. If the answer is X psi then when I hook it up I need to keep sizing my compressor up until it can generate enough air to over overcome X psi and overcome the amount of air being released into the line through my regulator. Hope this question makes sense.