I believed I read somewhere a few months ago while pondering this idea to give it a try that you can also hook up a solenoid to it also, thus having it not on all the time. Just didnt' want to get into all that stuff. The setups I'm using has been working for almost a year, so if it isn't broken don't fix it.
Yeah if you have good plant growth and minimal algae, no need to change your setup. A solenoid makes things easier if you need to crank up the CO2 for algae issues. You can crank it up during the lighting period with worrying about gasing your fish if, you turn it off when the lights are out. Increasing surface movement at night would make things even safer.
When your CO2 cylinders get closer to empty, do you notice any increase in bubble rate and or CO2 saturation?