it should be old enough for nutrients, but it looks like you may have given a smidge to much.

use fresh water next watering, and then resume with roughly 80% of the dosage.

also, i read elsewhere that the pH in hydro should be 5.7-6.2 roughly. you may consider double checking, although i doubt its the cause of your problem.
hybridlove420 Reviewed by hybridlove420 on . What Wrong with my leaves???? whats up, I am have a huge problem with my plants and its getting worse. If somone could please help me with this one, iwould really appreciate it. Heres the problem, as you can see. The fan leaves on the plants are getting yellow and have these brown spots with curling at the tips..whats wrong and how do I fix it?? AGE:3.5 weeks 400w MH Temp 78 degrees Growing medium- rockwool in claypebbles (in hydro) humitdy 38% Rating: 5