See what you did Beeā?¦..? You got everybody confusedā?¦lol. Yes you are almost correct but I saw no reason to bring in the calculations for luminance VS watts VS PAR watts. The watts per sqft is a rule of thumb and not the best way to calculate useable light and does not take into account the height of the bulbs and only works for HIDā??s. The conversation started out about HID so I just kept it there and made it simple. Calculating foot ā??candles or lux is a more accurate way to estimate the amount of light plants receive. This still does not really measure the amount of light the plant uses. For calculations purposes I use 10,000 lumens and the formula I=L/DĀ². You know how I grow so that even does not apply but itā??s a fair rule for 95% of the people out there. But in a literal terms you are correct I did quote a rule of thumb.

Eastwestconnect ā?? I just took down a 7x7x7 room and it had 9000w of HPS light all in cool tubes & 3 light movers. Your temperature is way to high. I ran one 10,000 BTU window unit AC to keep my room no hotter then 79f and I added humidity to bring it up to 80% during veg and then down to 50% until the last 3 weeks of flower when I take it down to 35-40%. I use Ā½ of my lights as sidelights not top lights. The increase of yield production is all in controlling the environment, using supplement COĀ² , and increasing light to all the branches, top, side and lower with direct light and not just reflective light.

Puff4twentynow ā??On offence meant but, no you will be luck to get 4 ounces of dry bud from what I can see right now. Iā??m just guessing but you donā??t have glass hoods on your lights do you? Is that aluminum foil you are using on your walls and hood? What is the average temperature under those lights? Do you monitor it regulary?