do you let the tap water stand for 24 hours before feeding it to the plants, this gets the chlorine out the water and makes it less harsh on the plants, by looking at the pics i would say its not nute burn, nute burn usually starts at the tips of the leaves, so what you have got is some sort of def, i have not had this problem yet so cant really diagnose for you, the leaves that are damaged wont get better, the def could of happened a while back and now its just showing up in the leaves,
sorry i cant be any more help mate, if you use your search engine and look for cannabis plant deficiency guide and then search you should find a few great guides with pics and this should help solve the problem