Is this Healthy?

Indoor grow, no nutes, miracle grow potting soil. Just started with distilled water. 4 weeks into flowering. All the fans look very very healthy and happy. But the leaves coming off of the main stem cola are curling. Feel slightly dry. Other than that and a bit of purple under the fan leaves, they really seem healthy. I am a long time smoker...short time grower. So ANY advice is appreciated.
Thansk,
EZ

what light are you using? it looks like they aren't getting enough light so they are dying. They might be to far gone if it's that. Try tieing the top of the plant down so that those inside leafs get more light. Or hang a couple CFL down in there to get more light to it, they can be 2-3 inches from the plant so they are great for getting light in those hard to reach places.

Yeah man, you probably have too much space and not enough light.