Plant turning Purple/yellow, any thoughts?

Hello everyone!
I was hoping to get some feedback on what may be causing my plants to discolour. I’ll give some details.

2x Blue cookies photoperiod, week 5 flower.
5 gallon fabric pots
4x2x5” tent
Happy frog soil
Spider farmer 2000 Light
Temp day - 23c, night 19c
Humidity 43-48%
Advanced Nutrients Grow Micro Bloom
Growtek Mycorrhizae

I’ve been feeding nutrients every third water, with about 4 days between waters. Water water feed, following the feeding chart I’ve attached. PH 6.2-6.5

just over a week ago I noticed some yellowing/reddening on one plant, near the center of the plant. A few symptoms, such as praying and curled edges let me know my light was too close. At 12”, my light was recommended for 16-18”

I raised My lights, but after another week some symptoms have gotten worse. My plant seems to be turning purple, and yellowing. I’ve done research and it seems I’ve either got a P/K deficiency...or a lockout and a buildup of salts. I’m not sure if I’ve given too much, or not enough. Or maybe it’s not this at all.


When I water with nutrients, I water until what seems to be 10-20% runoff. When it’s just water, I try not to get much runoff. There’s a chance I watered with fairly cold water last time, which I heard could prevent some P/Kuptake.

This is my first grow, so I’m having quite a hard time diagnosing this and choosing a path forward.

Thank you for reading my long post and providing any insight you may have!!

I have done the same routine with the sister plant and it looks much better

Looks like nure burn to me

Slight nute burn- purple could be genetics. Maybe back off nutes a bit. People tend to feed less than recommended most times. Looks overall healthy to me.

Have temps dropped at night?

Cold water + cold concrete ground?? + cold temps = purple due to the plants

did your house ac come on recently my buddy had the same thing and i noticed his intake was right beside the ac unit pumping cold air on his plants during his dark period.

It looks to early in flower for it to be throwing out those purples if it was genetic.

Temperatures haven’t dropped too much at night. It was getting down to maybe 18c at night, 23 during the day. I didn’t expect that to bring out any purples. And I’m on the top floor of apartment, so no cold concrete.
I also thought it was early for purple genetics to show, as well as it not getting so cold at night.

People on another site all thought it was hungry since I was only feeding once every two weeks, not full strength.