co2 help

how important is co2 for the last two weeks of flowering will it make a big difference the reason i ask is i ran out and i was going to go get a refill but im gettin low on money is it worth the 25 bucks for the last two weeks please let me know what u think

most worth it. but if you really don'thave the money do the yeast/sugar/water method.

we're using the sugar/yeast method and our plants love it. they perk up almost instantly whenever i shake the jug up.