Hi btownbudda,

As killerweed420 pointed out co2 allows you to be able to run higher temps but it is not necessary to run higher temps to see the benifits of it. Plus while 1500 ppm is nice level for higher temps like 90 or so, at 75-80 you get the same increase in growth rate with a lower amount, maybe 800-1000 ppm.

Here's a source for a couple of CO2 meters, the least expensive I've seen. I have and use the TIM-8 in my personal grow. And the PC-board one to interface to a computer holds much promise in setting up your own control system. CO2 Meter | Indoor Air Quality Products - Welcome Just saw the one on sale for $129.95, does alot for the money!
oldmac Reviewed by oldmac on . Need some advice for using CO2 I was just browsing through this site's FAQs and I noticed that it says you should keep the temp at 80-90. I'm on my second run with CO2 and I've been going broke trying to keep the temp at 75. The person who sold me my regulator said that the plants can take a higher temp with CO2 but still thrive at 75-78 and yeild better. Now I'm reading the opposite here. I'd love to turn off my ac but it makes me nervous. I'm 4 weeks into flower and everything looks happy. I would very much Rating: 5