Well don't agree. I don't care. But saying none of use grow for real is BS. Yeah I do have my light that close. I am sure the others that said they do also have them that close. What do you want pictures. I know I can provide some check below and i am sure others can as well. I have a perpetual grow going and have had it going for almost a year with no issues with my light that close. Telling someone to put his 150wat light 20inches away is nuts. Thats extremly far away for such a weak light. The plant with sretch for that weak of a light being so far away. Look closly in my picture. You can see a tape measue so you know I can messure now. BTW sence when is air blowing on a plant not healthy?
Yes. We would like pictures. The only way I can figure a plant showing zero heat/light stress from a 400watt hid at TEN INCHES, is for the light to be encased in glass, with double ended air exhaust. So yes- please do like everyone else, & verify your claims by uploading pics.
Because youre talking cfl range. If youre beig honest, Id guess that your bulb is likely old & not putting out the intensity it should. Because fans do nothing to dissipate light intensity. My QB288 puts out 1400 PAR wattage in te center at 12". That can only be processed by plants in full flower, with co2 added. Closer than 10" & the increase in PAR provides little to no increased gains. I use a 135 watt qb288 LED in the veg tent (Cooler than a 400 or even a 150watt hid) & even I was getting a bit of light stress (not heat stress) when I dropped it down to within 12" just to see what they could take. Luckily I was on it, & dimmed it down to 90watts before it caused any real issues.
Now when theyre older, into flower, the amount of light they can take obviously increases. But definitely be careful in seedling/veg. The standard "hold your hand out & feel the heat" method is more trustworthy with HID's. The new, high PAR LED's are so cool running, that you can quite easily give your plants too much light, without over-heating them. I "guinea pigged" a little 1week seedling just to see... At 12" away, it burnt the little lady pretty bad in only 8hrs & the temp NEVER went above 78 degrees! For seedlings, 5-10 PAR watts/ft2 should be fine... Double that for veg... But thats just my experience, & thats with leds.