so i'm growing 'green spirit' under 600w sodiums, they are 6-7 weeks old now from seed, still in veg 18-6, all look nice and green most of 'em are about 8inch tall 2 or 3 are 10-12 inch tall and nice and bushy but 3 of em are about 4 inch tall, are the 4 inch ones runts, they have tiny leaves...