Hey ShowOFF, I hope all's well in Russia. I think your 32wsf (watts per square foot) is more typical of other plants (tomatoes, peppers, etc), not necessarily for cannabis (grows a bit differently from other plants). From what I've read you'll want roughly 50wsf-75wsf since after 75wsf you'll see diminishing returns. You'll want a bit higher than 220W of actual output if you follow the 50wsf rule so ~325w. That said, typically a 600w is all you'll need for your 2.7'x2.7'x6' tent. Typically I follow these guidelines - 600w LED for a 3'x3' & 1000w LED for 4'x4' (this will provide enough light for the flowering phase). Do you have a link to the 1200w LED (250w actual)? That seems very low to me & may be a marketing gimmick/fraudulent claim since I've yet to see a 1200w LED that uses only 250W. My ViparSpectra 1200w LED runs at 524w-545w actual. Please send a link if you can & if you have access to ViparSpectra LEDs I'd suggest one of them since they get pretty good growing results. I hope this helps.