how close can my 400w aircooled get?
- Thread starter blizake54
- Start date
Jack Harer
Well-Known Member
I had my 400's almost that close without being aircooled. Remember, you lose footprint size the closer you get to the tops. I think that after a certain point, you get to a point of diminished returns.
tiltswitch
Well-Known Member
ul soon find out if ur leaves start to curl up at the edges....if it starts move the light away.....
hows are the 2 girls doing in ur opinion? they've been under the light 4 hours now. first time seeing a 400w hps were under t5's [4 bulb 4 foot]
depends on room temp, Good way to do it is put the back of your hand where u want to guage it....and u dont want to get them as close as possible when vegging, only flowering. U want to put the light where IT WILL BE THE WHOLE TIME OF HARVEST. u do not want to put the light as close as possible through vegging.
Total Head
Well-Known Member
i wouldn't put it any closer than 5 or 6 inches. i have a 400w hps and i let them get within 3 inches because they weren't showing any signs of stress and i got a bunch of bleaching of chlorophyll. i didn't think it was possible with a 400 but it is. i never let them any closer than 6 inches or so.
Jack Harer
Well-Known Member
Another thing to consider, you're losing up to 25% of your light to that clear piece of glass. So it's trade off. Less light, but closer, or full light and a bit further away. I know that I, personally, will never buy another air-cooled hood again.
I hear the glass also bsorbs almost all UVB which has been shown to benefit plants. As for the original question. I use 400w metal halides for veg and they can get really close. Trying to veg a mother, I had them growing into the light and it was only until the plant touched the glass that it got burnt.
Jack Harer
Well-Known Member
Nope. Depends on the composition and refractive index of the glass.
massah
Well-Known Member
Jack Harer
Well-Known Member
That's why I ain't replacing the air cooled hoods that the cops got. I had bought 4 Sun Systems, and after reconsidering everything, I'm better off with open hoods. I could buy 3 hoods for what 1 piece of fused silica or quartz glass would cost. They come with cheap leaded glass.
In reality, your average loss is only about 20% (It CAN be as high as 25%), but that is STILL a significant amount of light, more than enough to offset any gains by getting closer to the tops, IMHO.
In reality, your average loss is only about 20% (It CAN be as high as 25%), but that is STILL a significant amount of light, more than enough to offset any gains by getting closer to the tops, IMHO.
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