apparantly all cool tubes are 6" in diameter so i was thinking a Suncourt 6" In-line Duct Fan - 300 cfm would do it...
hmm, OK. I'm doing up some DIY cooltubes absed on the Pyrex "Bake-A-Round" heat-tempered glass tubes. They're supposed to be 3.75" OD.

Zandor has a great photoessay here on DIY "Bake-A-Round" cooltubes. I'm liberally thieving from Zandor's bit for my own.
Al B. Fuct Reviewed by Al B. Fuct on . 600 HPS Cool Tube Grow Light System 600 HPS Cool Tube Grow Light System is the cooltube wired to the right cordset and plugged into the ballast? i really want to order this system, but every company i email eventually tells me "no we dont wire the ballast to the cooltube"... anyone have one from bghydro that could comment ? Rating: 5