not sure on that,should be at least 20watts/sqft. some say HPS others MH.
Me I use both 1K each and a 1K MH for veg. for 81 sq.ft. 6-12 plants
currently using air cooled horizontals, but think better results
with bare vertical hanging. there was always a heat problem though.

Daddy
Daddynobucks Reviewed by Daddynobucks on . Daddys Garden Hydroton in 6"net pots, set in 6" netpot 5gal bucket lids with the net cut off so the 6"pots can be started in a ebb and flow tub 3-5 min on and 40-120 off, the max and min.without causing overwater wilt 18hrs floro twin 40watters for starts and early veg,then 18hrs veg under one 1000watt halide. 11.5 hrs flower under one 1000wattHPS and one 1000watthalide seeds and clones from clones from clones until bugs,then wipe clean start seeds again never have a mother. 5gal bucket grow Rating: 5