Day 60 leaf issue NL Auto

[Tyzoo]

Hi like title says I have some NL autos 3 all planted the same time in FF SF. These 3 plants have showed no signs of stress or deficiency throughout the grow. Feeding with FF trio half dose every other time I water. about 2 weeks or so ago started adding a half dose of cal mag once a week. Today I woke up and noticed a big change in the leafs practically. The other two plants do not have this issue. Probably Wishful thinking that it’s just fading a bit being almost 9 weeks old? First time grower. Last time I fed them just phd water 2 days ago with no nutes

 

[Tyzoo]

I am torn on if I should just give it phd water next, or if I should try to give it a little cal mag or continue to feed the normal nutrients I’ve been giving it thus far.