c02 generators are pritty pricey, the main drawback, plus you'll need a c02 meter to regulate it which is generally really exspensive
a easier way is to get a big bottle of any kind, couple of liters at least and pour in some yeast, no exact measurments as it will be relative to the amount of foliage your trying to boost, some tepid water and some sugar, which will gently release c02 all day, alot cheaper and near enough inpossible to suffocate yourself in the process
the main down point is the smell , it will range from fresh bread at the start of the day then it descends into a strong smell of old beer, some people tell you to pour a bit off everu couple of hours and add more sugar and possibly yeast . but i prefer to empty it every day and use fresh. otherwise the smell can gag a maggot after a few days
hope that helps
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