I have to again confess the error in the first post in this thread- I thought my trays were 4'x4'- they're not! They're 2'7" (820mm) square. However, it wouldn't be a showstopper if they were 4'x4'; plants on the edge of coverage might not do so well, but with plants in pots, you can move them around now and again to even out growth.
I agree, the difference is in the 8' of coverage for each one thousand watt light. I know you can cover a 6' by 6' area with that. I remember thinking that at one time. Idid see parts of the discussion on the other thread, so I was aware of the error If I had to convert to metric istead of our dumb system it would be the same, I would make errors too. Good to see you again from time to time. VV
i use the HTGS 1K someone recomended earlier - u can get them shipped in the us for about $350, with both types of bulbs, (hps and MH conversion), in a nice air cooled hood with 6" ducts...