No average. With the same bubble count I got 50% variation from the same tank, regulator, hose length, just different check valves. imagine when you change other things on the system....
BPS is only comparable between your system readings, if then.
What is the color of your diffuser at 2 bps? Go slow due to lifestock present, 1 exbra bps per day and monitor non-stop your fish. It takes a while for fish to adapt to live in higer conc. of CO2. But they do adjust their bloodworks and live well, just give them some time.
On hiatus till later this year