Required bubbles per second?

I need opinions on the expected bubbles per second needed to lower PH by 1 degree for a 130 gallon system from those with experience. For instance, based on your experience, should I require ~3 bps to achieve this? More? Less? My PH is 7.8 from tap, KH 6. Inline reactor, eventual high light / plant load. I am certain I will get the obligatory reply, "it all depends... just adjust it as needed," but I am looking for an experience based ball park figure. Thanks for any feedback.

EDIT: I should also mention I will be controlling CO2 on a solenoid with an Aquacontroller, so I intend to use the feedback here as a starting point, and increase that recommendation slightly.