Quote Originally Posted by LOC NAR on probation
It looks like a nutrient deficencies most likely from PH lockout. The new growth looks Ok so maybe problem solved already. Those leaves will not recoverbut they are not gone yet. Just leave them to die off natural.

You may need some cal mag plus.

And filling out the trouble shooting form will get you much more help. Nice pic's they help too.
yeah i think you are right improper PH can be the root to a lot of problems.