No co2 just flourish excel. Everything does grow pretty slowly but nothing ever dies. Not at home right now but at the most its only 2 watts per gallon. I just do the easy stuff, the only plants that make up the entire tank are java fern, anubias and bolbitis heteroclita ( fern). From what ive read i didnt expect the bolbitis to survive but it is, and its putting off some new shoots too. Its just regular gravel from petsmart too. It helps that none of the plants actually have to be rooted, most of the java fern is just attached to suction cups on the back glass.