Their description only indicates that the light produces 840 lumens and is equivalent to a 75 watt incandescent. Since it costs 16 bucks I would think that the more efficient option would be a regular florescent 40 watt shop light tube at 3000 lumens each.

Yeah...I have two of the ott lights...I jumped the gun if you will. I found you can get an 85w 5000k light for just under $30 and buy a clamp base at home depot apparently for around 9.00. I think I wish i would have not gotten the ott light. oh well.

Thanks for the feedback. Are Grolux bulbs still in existence?

I keep my set up very simple, I grown my plants on these coiled mercury lamps of 2000 lumens of about 35 watts each. The coiled bulbs and clamp base cost me about $25 bucks. My plants seems to like it.

Wher did you buy the coiled lamps?

I bought an OTT or 2 last winter. Too expensive for what is delivered. Better off with aPphilips cool and daylight combo (6$ for 3 pack). I had to call the OTT company for specs as they were not on the box. They were clueless. They don't last very long either.

I get my cfl bulbs at the link below. I like these guys. They are cheap friendly. well packed. I had one fritz on me, the fedex'ed me another right away. I use the 5100K 42's and the 5000K 85's. My plants took off like rockets!

Honestly, I cringe at tubes now. They are more expensive to run too but I grow more than 200 plants. Neccessary evil in z-5. I use the cfls & tubes together . (4 tubes and 2 cfls shot in from the ends or from the front) when I have to instead of overdriving. Even with 23 W cfl's, It delivers about double the "sun power" in that config.

Clara

Here is a link that might be useful: Lightbulbs Direct website

I bought my coiled lamps @ Wal-Mart. $9 dollars each and 2700 lumens @ 45 watts.

Thank you for the link! Now to fly them by my wife!