Halides & Heat
 

Other than the warming effect on your tank water, is there any benefit to cooling MH lamps? Do they run better/longer when actively cooled like T5 HO? I recently installed a number of small fans to cool the ends of my T5 HO lamps since this is reported to make them last much longer and run more efficiently. Just wondering if the same is true for a typical 250 watt SE MH lamp, or if it's better just to let 'em run as hot as they want, provided they don't heat up your water to the point of requiring a chiller.

Good question...I'll tag along on this. I have never tried to cool off my Halides but have run a fan to blow air from under/on them,to force the air away from the tank. As I run my house cooler then most I have never really had a heat issue.

That's essentially what I'd been doing as well and found my evaporation rate was getting out of hand, so now I only run the small fans blowing directly on the ends of my T5 HOs.

Yea thats another factor to consider. My evaporation was crazy as well,thats why I moved my tanks downstairs where its alot cooler. Plus I could hang some of my jerseys on the wall as well :)

Did a bit of a net search on the subject & there's plenty of techno talk about how MH lighting works etc., but not much on the cooling aspect or if it's required/beneficial. Maybe there's more info to be found with our horticultural friends, although they use even higher wattage lamps, generally 400 plus. I did come across a site that showed pendant/reflector housings which accomodated fair sized cooling ducts through the sides. Cooling for that application may be necessary to keep from cooking the plants, not necessarily for lamp efficiency or life. I'll search a bit more when I have additional time on my hands. I guess it might help if I had some friends with grow ops in their residence!

lol!! Won't be long till grow ops go to led for longer life, less heat, and less power consumption just like the "reefers"!!lol