I want to offer an option for the MVP, as well as anyone who wants to "upgrade" their PFC to HPA a way to do so. I appreciate all of your help so far and would now like to start working on this very small and simple HPA system. Keep in mind, my goal here is not to create the "holy grail" high-pressure aeroponic system. My goal is to teach people the requirements of a system and enable them to build their own down the road or at least have a way to get started for ~$100.
Pump - I know you said this would be loud, but frankly I'm willing to live with it for right now).
Pressure Gauge - I know I'll want it when determining it for myself, but once we have it calibrated is it necessary? Do you think adding a pressure sensor hooked to the Pi would be possible? Has anyone had experience using Pressure Sensors with Raspi?
Accumulator - Will this be sufficient? I was also looking at DIY options, thoughts?
Solenoid Valves - Would this be sufficient, or is it too flimsy?
Misters - I plan to use a Hollow Cone mister. I'm looking at using BETE nozzle number WT10, which at 100 PSI provides 0.00266 gallons per second. My reservoir should be around 20 gallons of volume, with about 8 plant sites. Based on @Atom's recommendation I want to deliver 0.02ml of liquid per gallon of volume for young plants, that's around 0.000105669 gallons of water per misting interval. Perhaps I'm doing something wrong with my math here, I'm still uncertain on how to deliver such a minuscule amount of water though. Would it be smarter to use a misting ring? or should I be looking for T fittings like this that I can then attach nozzles to?
Tubing - I plan to use PEX 1/4 tubing I'm trying to avoid brazing or the user being required to have metal cutting tools. Secondly, what diameter tubing should I use? I know the pump starts as 3/8, my accumulator is 1/2, and the solenoid will be 1/4 (in theory I could go 1/2?). I want to go down to as small as 1/8 when I'm inside of the unit though (I think?).
I know that's a lot of questions, but I'm learning here and I think this is one of the areas that deserves focus and would really appreciate feedback/help. If anyone is willing to prototype one of these systems as well that would be a major help for the MVP project.