2 worked for me, worked great, I found with
blumats, since your getting very little run off, it was good to water with RO occasionally , I did feed 2 days R0 third. I lower strength nute solution would probably also work, how ever u want to deal with em
Only thing I didn't like about
blumats was the gravity feed part, elevating a 100g res was impossible so I had to set up a 5g bucket with float valve and pump, worked well tho
Edit cuz my iPhone spellcheck like to turn
blumats into blunts... Go apple