I tried that method I would personally have a rubber tube coming out if the too and into another just full of water to try and filter it. Made my tent smell like shit, like unbaked bread still has that smell kind of. I'm getting proper CO2 next time, with a tank, regulator and meter, it'll be worth never smelling that trash again lol
Too much of an investment and too little return for me in 3x3 tents.
A couple tips for anyone making their own co2 though:
Dont ferment grains or just sugar, ferment fruits instead. Grains will always smell like bread and sugar has no smell so the yeast will be the only thing to smell.
Dont use bread yeast. Use champagne yeast. Bread yeasts smell more bready. They also stop converting at around 10% or so. Champagne yeast goes up to 19 to 20%
Hope this helps any of you DIY guys and gals