Is it a deficiency or heat? (27-34) I have another...

Took a look at your diary which gives MUCH better pictures of your concern than this one does (it's always helpful to link your question to the diary... the way you do that is to ask your question FROM the diary... you can find that at the bottom of the diary page). Couple of things.... I think the clawing is a nitrogen overload - and before you say "but I give all of them the same thing" I will tell you that individual plants can and oftentimes DO react different to the same care, same nutes, etc... you need to focus in on the individual and say "hmmm, she doesn't seem to be liking _____" Second thing I see is that your lights are too close to your plants... they should be a lot taller but you're not allowing them to stretch because they simply don't have to... raise the lights to at least 18-24" above the plants and you'll do a couple of things - you'll make them grow taller as they stretch for the light and you'll probably cool off the area right around them which, with these damned heat waves everyone is having to deal with, is probably a good thing. Your temps aren't TOO high but they could be lowered. Do you have a fan or two going? This will help reduce the heat. Third - your humidity is pretty low but not awful at this stage. If you can, raise it a bit by hanging a wet towel or two in the tent... try to get the humidity up to 50-55%... When they go into flower, you'll want to drop that to avoid bud rot or fungus. Good luck and enjoy the journey!