Leaves soft, slow growth, and purple stems - root issue or cold substrate?

@Ultraviolet not only mulder chart 😤 look at the leaves, the color, curling and hlorozis of top fans, burned tips and edges just P def would show different sings in dif places 😎

hey 👋 In my opinion, it's just a slight cold. However, you should stop using Voodoo and increase the Calmag to 2 ml.

Phosphorus is negatively charged and is not part of the cation exchange competition at the root surface, which is why K+ primarily affects other cations first. If there was so much K that it caused the antagonistic effect of locking P in a medium, then it would affect other cations like magnesium Mg2+ and calcium Ca2+ before it ever got to phosphorus P because of competitive uptake at the root surface. You just basing your entire answers on an antagonistic mulder chart? 👏

don't u have thermometer? oxigen guy 😅 nope watering/light stress 😂 nope 2 options - P def - K excess and P lock (more likely)

Looks more like a cold root zone issue to me the purple stems and soft leaves fit that perfectly. Try to keep root temps around 22–24 °C and make sure the medium isn’t staying too wet. If temps are fine, then it could be a mild P deficiency or a pH imbalance slowing nutrient uptake. Warm up the root zone a bit and it should bounce back fast

Could be a sign of s-deficiency, but overall health of leaves, beside droopiness, points more toward genetics as to why it's red-stemmed. The droopiness can be any number of things. Poor watering habits probably being the most common and obviously overlaps with root issues or a subset of it. was it mid to low 60's F? If not, probably not temperature - easy to rule out. too much light? If giving too much light plants will be droopy the last hour or more etc.. Based on how close the leaves are at the top (some, not all), i'd wager this might be the cause. (node spacing informs about light intensity) The back left plant might exhibit this, but need closer look. Watering-- simplified basics 1) fully saturate (plus, 10% runoff if soilless) 2) wait for appropriate dryback and repeat if not doing that, could definitely contribute or cause droopieness / and a whole host of root problems. Dry pockets are bad news over the long-term.

At its core its a lack of oxygenation. The reason why the oxygen is lacking can be for many varied reasons, cold, drought or oversaturation, basically anything that fuxks with phosphorus, its availability and uptake. Oversaturated medium, reduced oxygen waterlogged soils =anoxia. You will have a better idea if it's drought or oversaturation. Given she is lime green too indicates iron is messed up too. Waterlogged soils are often low in dissolved oxygen, which promotes conditions where iron (Fe) and manganese (Mn) phosphates can be reductively dissolved, increasing the immediate solubility of P. (Leaches out of reach of roots)