I'm using this method on my current grow. The smell is kinda bad, after a few days of fermenting, but I guess that just means you know its working. Supposedly this is how beer was discovered - Yeast fermenting in a sugar water solution, which creates CO2 and alcohol.

Does anyone know how effective this method is, compared to other methods? For instance, how many 2 liter bottles would it take to match the air CO2 concentration maintained by expensive tanks and regulators?

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