I use an NFT system, two of them to be honest...total surface covered by both =12sqft, i have 2 x400 hps as well but you can grow a SOG only using one....these can support medium sized plants, i think up to 3ft tall give or take....it's my first grow in hydro, my previous was in soil and even i had great results (strain twilight) i chose hydro for being faster and more productive yield wise

take a look at this pic of how my plants look like after 16 days in the NFT.....i faced some minor overfeeding problems but the other good thing is that with hydro it is faster than in soil to diagnose the problem and correct it using mainly two instruments...the pH & the EC/TDS testers....

take care

NGOS