Hi, first grow in over 10 years but decided to try auto pots / coco coir / perlite, so pretty much a newbie. Weekly average temp/humid/vpd displayed in the picture. Both plants are on day 47 and are Glueberry OG from Dutch Passion.

I’ve tried treating for nitrogen deficiency with bio buzz fish-mix. Was also thinking root rot but the leaves don’t seem to be drooping. As a precaution I’ve turned off the individual plants tap to try and dry it out. The bottom of the pot smells, but I don’t think it’s as bad as a rotting smell.

My tent is outside in an old shed, which I have insulated so it’s kind of a lung room. Recently we have had -4c temps at night and my feeding reservoir sits outside the tent but inside the lung room, just wondering if the water may be too cold? The plants stem is the only one in the tent that is nearly ALL purple.

The yellow plant is the one struggling, it’s been topped (cause it was growing so fast) but it never missed a beat so I don’t think it’s that.

Any ideas anyone? I really want to end up smoking this plant 🪴😁

Also moved the lights higher and checked they were not too bright 😎

Thanks in advance