Many moons ago, I thought I would jump on that "co2 Bandwagon". I've always been that type of guy that figures "Every little bit helps - right?". So I checked around and did some research, I came up with the following:
1. Adding co2 @ about 1,500 ppm allows overall yield to increase by up to about 50% (more or less). But what they don't tell you is that you need to use more lights and more nutes (in a bigger space) and water more often.
2. At that time, monitors and regulators were seriousely expensive, they're still not cheap!
3. It occured to me that since I needed to upgrade everything to use co2 anyway, why not just upgrade everything by 50% and forget the expensive eguiptment!
In my book, adding co2 only makes sense if you are:
1. Absolutely stuck in a very small space and really need to maximixe your yield - no matter what!
2. Already running a big operation and the cost is not an issue.