i currently finishing my first soil and about to start my 2nd. i hav 7 NL and Ak47 in dixie cups but i wanna do a hydro setup. first this would i be able to change to hydro eventhough i started soil? i mean there not in that much soil couldnt i just wash it off. 2nd my box is 4'hx4'wx3'd. i want to get a 3'x4' flood and drain or a 4x2. i also plan on getin a 6" air cooled tube for my 400 watt hps and a 4' light mover. since im getting the mover could i get the 3'x4' tray or should i just do the 2x4 cuz if its 1'x1' per plant and a 400 wat will only do 6-8 plant then would the 3'x4' be a waste? thanks in advance for the input.