Thanks! Yep, it sure is bud. Been using since I started growing, so cant say for sure because never grown without. When you have a tent the size like mine you give them co2 everytime your in it. This just gives some extra, I dont have a sealed room setup lol. I dont think you will get your money back with the expensive setup. They're cool and added co2 will increase your yield, but you'll spend more on your setup than it will increase your yield. It cost more than it should just like everything else so at the end of the day I dont think it's worth it. Now my 2L bottle cost almost nothing and gives me co2. Jar of yeast is like $7, get biggest bag of cheap sugar like $10. Last for multiple grows, going 2yrs on yeast jar so $17 over like 2yrs. Way cheaper than setup, seen folks use dry ice too if you can get it. Nothing wrong with co2 setup but I'm a budget grower and just not cost effective in my eyes. If I had 300 plants I would use dry ice, that would be to many bottles to shake lol.