c02 level
 

Ron: Thanx for all the helpfull info. I called the store that sold me the cd-3 genorator and they were very little help.They suggest 30 mins. on 30 off. With in 3 days the plants were curling/dring out.I assume to much c02.Now I'm trying 30 mins. on 4 hrs. off hope that will fix the problem. Is there any way to measure c02 level without a CDM-1 sensor{determines atmospheric c02 value}

Wormsway.com sells an inexpensive thing to measure co2 but only once then you have to buy refills to measure again. I have never use it so I don't know how well it works. I have just been guessing for years about how much co2 I am using.
Ron