Hard to count more than 3-4 a second.

A well run large tank will take longer in general to respond and accumulate CO2 as well as dissapate, say a 20 gal vs a 200 gallon.

That's why ADA suggest multiple diffusers rather than one big one on larger tanks, you can do the same for a small set of internal; reactors and externals as well taking water in/out of a larger tank.

Regards,
Tom Barr