You shouldn't run co2 all day. You should turn it off at night because plants don't use up co2 at night, so you will be basically be wasting the co2. High levels of co2 can harm fish. That co2 regulator in the link I believe comes with a solenoid. The solenoid can shut off the co2. You can put the co2 on a timer so it can shut off on its own, so you won't have to shut it off manually everyday.
I can keep it on with my lights right? Im not home all day so i usually turn it on before i go to school call my mom to turn the lights off and then turn them on when i get home till i go to bed and i usually get home after dark
Before I had my controller I simply used a couple cheap timers, I started CO2 an hour before lights come on and turn it off an hour before lights go off, this allows the CO2 level to build up a bit before the lights come on and allows the plants to use up remaining CO2 before the lights go off. And as posted above, when you move to CO2 you really have to find your balance between CO2, ferts and light, this is always important but even more when you start higher tech setups. Good Luck!