Pistols turning red week 5, curled down rusty red and yellow leaf?

Like it says.

Im using General Organics in Roots Organic soil. The plants are too big for the pots, ( I had to veg a lil longer then expected due too... life ).
Temp: 70-80f, Humidity: 50-55% all the time.
600w HPS in a 4x4 space.
HUGE charcoal filter / fan combo.

This aint my first rodeo, i have done this same way for three crops now an haven't had prob's until now.

I gave em some CaMg+ from botanicare (I love that stuff) I was using the CaMg from G.O. (its not very strong) in-fact G.O. is not very strong at all I have been feeding full strength every water just to avoid a deff.

I DO NOT PH ANYTHING THAT GOES IN THE SOIL. It says that PHing is not supposed to happen right on their Feeding schedule, and from what I know you cant PH organics any way the microbes do that for you. BUT I DID CHECK IT, ITS ALWAYS WAY LOW LIKE 5.0. ( I KNOW SKETCHY, BUT IT HAS WORKED GREAT IN PAST)

COULD THIS BE A MOLD ISSUE OR IS IT CaMg?

Why are the hairs turning red already-week 5?

Also when do yall "lollypop" your plants? I do mine around week 2 or 3 in 12/12.

Thanks to all +rep

I like to clean up the bottoms where I want them before I flip. Then I maintain the canopy by taking out the big mature fan leaves. The main reason for this is to let lower nodes get adequate light. The yellow leaves are most likely from your plants being root-bound. Flip them in to 12/12 smaller, or put them in bigger pots. Cal-Mag looks more like a curling in and down simultaneously. Like a claw. The pH problems usually result in deficiencies. You're basically lacking bio-availability because the plant can't absorb the nutrient at that pH. The soil you're using will balance that out, and that makes me think they are root-bound.

Hope this helps,
Neb