thesecond set of leaves are well on their way at day 8 ..... i just finished building my new grow rooms today ... i have a 4x4x8 flowering room with 2 600 watt dual spectrum hps and a 4x4x8 grow room split at 3 foot up , bottom part is for clones with 4oo watt of floros and the top bit is for mothers with a 400 watt dual spectrum hps. i have 2x 125mm ruck fans with carbon filters 1 for each room and 2 small 4 " extractor fans drawing air into each chamber.