You can combat stretching by adding some Bushmaster. Be careful though! It is VERY strong stuff. I use it as a foliar during veg to compress the nodes. Since I have limited space, I often have to use it the first week of flowering. The plants stop instantly and make the buds like softballs. It also throws the plant into flowing a lot faster. I use it at about 1/2ml / 1gal. with a 75% reduction in ferts when using in the res. As a foiliar, use with Penetrator and PH the solution.