How low can I go with 1000watt light

I'm using 5'x5'x80'' tent with 16 5gal. buckets. How low can I go with A 1000watt light. The tent is well vented. Thks Richard

depend on you have a cool hood or tube on it ?

I would say maybe 20-22" with out and maybe 15-18" with, try to keep your hand at canopy level for a few minutes, if its feels ok for you it will be ok for your plant`s (look for uncurling leave edges for a sign of heat stress)

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