My Mephisto's have ambered up. As
@Margahooja replied it takes time.
You could easily do 6 girls in a 4x4 tent with a 600w and cfl side lighting. Just keep an eye on the grow area temp. I am running a 400w Super HPS in my Stealth Armoire. I try to keep my grow area between 75F-80F. Then my Den's room temp needs to be 10 to 15 degrees cooler. A Den's room temp of 65F (rather cool) the grow area will be 75F. Keeping a healthy grow environment is very important. Cool fresh air, gentle breeze, plenty of fresh water and food. That's it. I try to mimic the seasons inside. Spring and early Summer in VEG and Late Summer into the Fall in FLOWER. Oh one other thing...keep the grow area clean. Even out side the tent. Vacuum your rugs if the tent is in a carpeted room. Sweep up and keep the dust to a minimum. Clutter breeds disaster.