Nothing i posted was sarcasm. I meant it all. If you dont know that CO2 increases photosynthesis rate than id call you an idiot. nothing sarcastic about that. The only insult i had was directed toward you specifically for being such a dick with the search button talk. If you re read my first post i wasnt asking about the use of CO2 i was asking about how people have their systems set up and what works for them and alternatives people have come up with besides valve systems that they've seen success in, something you cant always find with a search engine. This forum to me is much better than a search button" because you have the ability to discuss and learn from others who have tried it or have more experience with it first hand. A true resource. If its a waste of your time to comment and you think i didnt do enough initial research then just pass over it..no big deal. no hard feelings here. peace and good growing.