Trust me - EI is a cake walk compared to dosing in a reef tank!
Most folks who use pressurized CO2 do so with a solenoid and a timer. CO2 typically on 30-45 min prior to lights on so there's a good concentration in the water column to be used by the time plants start getting all the light. And off about 30-45 min (these times are just an estimate, don't hold me to that) before lights off so there's no over abundance of CO2 in the water after lights out. That really helps prevent gassing fish over night.
For those who run CO2 24/7, many use an air stone at night to help gas things off and prevent harming critters.