Good point turtle!!

The loss of lumens you hear about jdog is if there is no bat wing or reflector to direct the lumens from the top of the bulb (if you hand it horizontal)

Hoods have that reflection point and cool tubes don't as a normal rule. You can add a bat wing to them though.

The loss through the glass is not a worry either with either light setup.
Zandor Reviewed by Zandor on . Cool Tubes Vs. Cooled hoods... I am thinking about using cool tubes in the future. And what I was wondering is how many lumens do you lose threw the glass tube compared to a regular cooled hood. Is it the same. I heard the cool tubes lose more lumens. But that sounds like bull to me. Because it seems like you could get a cool tube really close. Like inbetween the plants. And standing upright and connected together. Fuck it I'm going tubing!:thumbsup: Still would like to hear anyones opinion who used or uses them. Rating: 5