help i dont want my buds to die!

is this zinc?? how do I fix this??

from reading a lot it looks like nute burn. I would flush.
I'm sure more advanced growers will tell you for sure.

also a list of what you are using and feeding schedule, ph, ppm's and all other relevant information will help you get better answers.

4 weeks of flowering. using jacks bloom booster for a nute. nuted water is about 6.4 ph from a dropper test.

definitely nute burn. flush flush flush. the bloom booster is used usually in the 2nd month. get a base nutrient

what week are you into flowering??usually flowering nutes have very little to no nitrogen in them, and also the plants concentrating on flowering so the leaves may die off.also towards the end it may sometimes start to use all its remaining energy to bulk up the buds
just an suggestion of what it could be

happy growing

It looks to me like you are using cfl lighting and the light is not penetrating the lower foliage and add that into the fact that most plants usually die off towards the end like rinny said and there is your problem, no problem. heh
The tips of your leaves do look like the beginnings of nute burn but if it does not go further than that I would not go flushing like a mad man. Just use a little bit less the next feeding, not much less just a little. My guess is you saw the defecienceies and stepped up the nutes and they just burnt a little. I have burnt my plants much worse and they still finished just fine. heh

Just to update you guys on the first post. The first picture was yesterday. second a couple days ago, and third a week ago. It has gotten worse

Please post some pics for everyone to see. that way, they can help you in assessing what could be wrong in your grow.