I'd do at least 6.

I've got 2 250 watters and 6 works fine for me. If I TRIED keeping them short (which I'm letting them flourish) then I'd probably do 8 or 10.

Good luck..

<3
The Grim Reefer Reviewed by The Grim Reefer on . EXpert Help please~~~~~~ howmany plants can i grow under a 400w hps with maybe 1 or 2 cfls and foil on the walls ? white widow white rhino big bud i just need a total number please:rasta: Rating: 5