Light is not air cooled, it was at 12 to 14 inches as recomended. Heat wasn't an issue, it was the lack of performance
The brand of bulb I'm using is IPower
The MH bulb is 6000k and the HPS is 2100k
I do have a dimable digital ballast 150-250-400
Maybe I'm just expecting better results than I'm getting after hearing so many people praising the MH/HPS
advantage in growing?
I never actually addressed your question about bulbs. Like others have said though hortilux makes the best spectrum HID bulbs. However when I've tested other bulb companies I have never seen the major difference others claim.
Personally I think 12-14 inches is to high for a 400 watt. How much space where you trying I cover with it? A 400w is only gonna really cover a 2x2 area with good light.
I run my air cooled 1kw about 12-14 inches from my canopy. In all the years I've been growing I've only had one plant get bleached from getting to close and it was because I was gone a few days.
I don't actually care about the spectrum as much as some people talk about it. I'm not satin it doesn't matter. My 400 was a mh with a cheap HTG bulb and it grew bad ass rock hard buds. It did that because I kept it nice and close to the plant it was growing.
The hood being air cooled meant I could have the plant almost touching the glass for the light. My bulb was probably never more then 8 inches from the top of the plant it was over.
I haven't used LED yet, but from all my reading and watching others grow with it I think the biggest reason it gets a bad rap is because people try to use science to act like they don't need to pull as much wattage. If/when I switch my 1k hps room to LED it will be with as close to 1k actual wall draw watts as possible. If I switch it won't be for more "efficiency" like so many LED guys talk about. It's gonna be for more even light coverage. If I can use the same wattage but cover my whole area more evenly with high intensity light I'm certain yields will increase.