Your right the smaller they are the more they strechin height. Seems like I get alot more from a bigger plant when flowered. What happens is the smaller the lights the smaller the plant when you flower. Tha light can only penetrate the top one third, so they start small. I am going to try 2 foot and 3 foot to see the difference. I read a guy on here was getting 4 pounds off a 1000HPS and 4 plants. Awsome.