Youd have to get above 1500 ppm which is optiomol co2 which to even get there you need co2 tanks or co2 generators. 1 2l bottle will only give off the slightest amount of co2 more or less not even affecting the grow. A 5 gallon buckets in a small space maybe a 2x2 by 4 foot area would show some increase in growth.