Setting up a CO2 system for your aquarium can greatly benefit the growth and health of your aquatic plants. To set up an aquarium CO2 system, you will need a CO2 cylinder, a regulator, a bubble counter, a diffuser, and airline tubing. You should install the regulator, connect the bubble counter and diffuser, turn on the CO2 system, monitor the CO2 levels, and adjust as needed. Always read the instructions carefully and follow safety precautions when handling pressurized CO2.