In one final twist of irony, as you begin to increase carbon...

In one final twist of irony, as you begin to increase carbon dioxide levels to maximize plant growth you will reach a point where temperature becomes the limiting factor. In order to benefit from the highest levels of CO2 supplementation (1500-2000 ppm), you actually need to run your garden area warmer than normal (80-85 degrees). On average, plants will also require an extra 30 watts of light/sq.ft. (80-100 watts/sq.ft.). Plants will use extra water and nutrients under these conditions, so make sure they are available!

http://www.jasons-indoor-guide-to-organic-and-hydroponics-gardening.com/plant-growth-and-carbon-dioxide.html