yeah I didnt meant to ACTUALLY bubble the CO2 into the res. I want to have the CO2 tank and run the CO2 in through some copper tubes THROUGH the res and then out the otherside, where the CO2 would be released into the room and enrich the plants on a specific time schedule (I have a CO2 controller). I am hoping there is enough cooling by just having the CO2 travel through 2 copper pipes submerged in the resevoir water.

I am only thinking about this because I am doing CO2 and I need to cool my res, and I figured this might be a way to kill 2 birds with 1 stone.

I am going to play around today and see how much CO2 needs to be released for the hose (or a copper tube) to get cold. I also was thinking that since the actual CO2 tank also gets really cold, that I could put my hydro resevoir into a larger resevoir and then I could just stick the CO2 tank right in there with it for further cooling.

PS. Like your picture Stinky, thats what I was talking about. I dont want CO2 inside the actual water, cause yes I am aware of carbonic acid. I already have air pumps for bubbles.