New lights new problems

I switched my mother's to cmh recently. Before they were under 400 watt mh.

I'm seeing the leaves slowly start to yellow from the middle of the leaf segments. And the veins and top of the stems are starting to turn purple.

They are in some potting soil with horse manure and top dressed with an amendment mix the same day the lights were switched. I haven't had any issues untell I switched to my cmh.

I usually water with just tap water and if needed some veg nutes.

I've been reading that it could be ph, calcium or mag. I don't think it's nitrogen.

I just watered with a tea if hopes it will help the roots. Next time I plan to add some cal mag, Epsom salt and some house and garden nitrogen that I have kicking around. And ph'ing that down to 6.4.

Any advice?

P.s. please ignore the two fried plants.

Stick with your plan for cal mag. Consider nutrients .