What are y'all using for cooling these said MH bulbs 2-3" away? Portable A/C? Central air? Imagination? and btw that light wasn't even on lol i think you tryna fool me lol and 75$ for that bulb somebody got over on you. lol
So some exact information.. to which I am sure you will have some witty retort. I forgot to mention that it is a conversion bulb that puts out 55K lumens. Here are some pictures for you... mind you I just moved some younger clones into the middle.. and those are propped up as close as I can get them without them falling over. As you can see.. and others have in many of my posted pictures, that I literally keep my light 2-3 inches from the plant tops. The hood is large, vented at the top, but has absolutely no cool tube nor is it ported for use with a booster fan.. like I said it is 12 years old. There is also safety glass on the hood (which if you are at all familiar with thermodynamics you would know) that absorbs and transfers the heat away. On top of that there is a window box fan adjacent to the closet and there is a 16" oscillating fan pointed at the glass at all times.
The post with the HPS off was not mine...
Also as I said before.. I have a 1000w HPS for my budding room, that is in a cool tube with a 240cfm booster fan , as well as enough exhaust to exchange the whole room's air volume in under a minute. Even in that environment with oscillating fans as well... I can't get the light any closer than 12-14". Different lights different restrictions. I don't have to prove anything to you... I will continue to keep my eyes and ears open and learn from others (even though Ive been doing this for almost 15 years)... that is the spice of life, and that is how one learns...
Peace out
Oh and I say keep your enemies close.. but your grow lights even closer