A question from a fellow grower:
i cant afford a co2 set up but i read that you can get seltzer or pure carbonated water and slowly poor it into a spray bottle and spray the under side of the leaves . would that work ? let me know thank you .
some people claim that carbonated water does wonders for plants. 
I think this falls undser the; "I have to see it, to believe it’ Category.
There are people on YouTube who mix 1/3c sugar and a packet of active yeast in a 2-liter bottle of warm water and leave it in the grow space with the lid off til it starts to smell like alcohol which they report usually takes a couple of weeks. I’m just waiting for my seeds to germinate for my first grow so I couldn’t tell you first hand but I’d intended to try it because it’s cheap enough and I don’t see the harm.
ETA: I suppose it could attract bugs but then again it could trap them in the bottle as well.
This is one homegrown recipe. Not a bad idea, but it must be the right type of yeast. Further research required.
They just used the packets from the grocery store baking aisle. Nothing special.
I’m telling you…It does matter. Best way to learn; Do it your way. Peace