trouble in my backyard - top leaves turning yellow

[johnb1963]

hello friends, yesterday I get home from work and check on my baby girl, and i notice the top leaves on three shoots are partially yellow, wft? it has been 90+ all week, so i wonder if that's the cause? any thoughts / advice? shes about 30 days from harvest.

 

[johnb1963]

one additional note, she is an Indica plant, so I have always kept the water ph between 6.2 - 6.5, but I read an article that says during flowering, drop the ph to 5.5. so i did. I watered her yesterday morning before sunrise, like I always do, and when i came home, is s the first time I've had those yellow leaves. do you think the lower ph had something to do with it?

 

[Rwise]

If you are in soil, PH to 6.5 - 7.0