See linkie

Here is a link that might be useful: More than you ever wanted to know...

Thank you! For some reason I thought it had to do with the spectrum of light.

I use T8 -- cheaper than the T5 and uses less energy than the T12. Plus the T5 seem just a tad too slim to try to get 2 seedlings under both bulbs back to back.

Kevin

I agree with Kevin. T8 is more economical AND energy efficient too. A 48"-double tube system costs about 20 bucks, complete, wired . Just plug it in. I have two of them and I have to get another one soon. @ 32w/bulb (64w two of them) uses just ONE kilowatt a day. They are really dandy.

UP date:
I bought the third one:
-- $12.95 the unit
-- $9.95 >> two Daylight Deluxe bulbs
--- Plus tax ===Total : $24.95

This post was edited by seysonn on Fri, Feb 28, 14 at 3:03