Solenoid cycles on CO2 to reactor: how often is too often?

[sphelps]

I tend to have the opposite thinking, I'd rather it cycle more often than stay on for long periods of time. IME these solenoids typically fail off since they are NC and when left on for long periods they produce a far amount of heat. So seems to me having it stay on for longer periods is more likely to create a failure, especially one with it left open. I use to run my bubbles fairly fast for this reason, the valve would only kick on for 30 seconds or so before shutting off and then would stay off for longer periods until the pH recovered. While this did mean the reactor pH would drop a bit more than you guys are seeing it still maintained near perfect levels in the display.

I also seem to recall setting my target pH lower, closer to 6.4 as suggested by the media, which allows for a slower effluent and more efficient use of the C02.