I also haven't had good bloom stretch . things I have changed ,got a light meter ,ph meter both after reading Nebulas tutorials on both , I flipped the switch 1.5 weeks ago they have grown 4 inches since then also I dont keep my temp stable it fluctuates between 50 and 75. I didn't correct that because I'm building a new room after my girls finish up in this one. but keeping the light at the right distance away so all of my buds are between 45 and 85,000 lux has made a big difference (when I first checked it I had the light so close I was giving 110,000 lux to my plants burning them. and the ph well my water is at 7.3 this grow i"m growing gorilla glue and they quit feeding for a week because ph was to high . now they use 1 gal every 3 days so it makes a difference, I will see if temps make a difference next grow