Yellowing tops

So epsom salt should help with this case ?

Ph 6.5 I don’t know ec and ppm I didn’t feed at all (clone) I just transplant ( second week little bit root zone and power zyme hesi )and water after that I use Biobizz all mix for flower. on veg I used plagron light mix I hope this gonna help

What are you feeding them ? I would say some of it is preflower and nothing to worry about though a nitrogen deficiency usually shows in the bottom leaves of the plant not the top so that would make me lean more towards a ph fluctuation or a nitrogen toxicity though without knowing what your feeding its pretty hard to judge. it could also be a lack of light if you have had cloudy weather for a few days this could cause similar symptoms but will clear right up with a few sunny days. If your ec is say over 1.5 i would assume its too much nitrogen rather than not enough :) Hope this helps and best of luck :)