The rule of thumb I use is to carbonate for 70 psi-days. Since I pour at 10psi that takes 70/10 = 7 days to properly carbonate. If I'm in a hurry 2 days at 35psi (2 x 35 = 70) will do. Or 3 days at 24 (=72. Close enough). Those times I accelerate the process I disconnect, release pressure, hook...