It's not a watering problem I can assure you of.that much I have a moisture meter and I only water a 8 oz cup a day and add when meter drop.below 6 its.gotta b anute deficient of something but I can't make out what it is these are both purple strains and out of 32 plants theory the only ones seeming to do it. I have 13 strands going right now and these ones are the only ones effected
Those are the worst watering habits to have. That is how you cause over watering. It isn't about "too much" water. It's about "too often" watering.
Lift the planter. Is it heavy? Yes. Don't water it.
Lift the planter. Is it light as a feather? Yes. Now you can water it.
No need for the Great Divining Rod. All you need are opposable thumbs.
Water to complete saturation. Allow 20% of what you add to drain out the bottom as run off. Collect this run off, do not let the plant drink it back up.
By the look of the plant it would appear to have a bit too much nitrogen, and definitely not enough Potassium. This phenotype might be sensitive to heat as well so keeping it near a fan, or in the corner, might help it out. The second picture resembles that kind of "is it mold? is it phosphorus?" problem. So long as the issue has stopped I don't think I would key on that as the primary thing to diagnose.
The rich dark leaves, general "hinge" look they have while curling down, and non-uniform growth indicate to me a nutrient imbalance.
I would flush the media and focus on trying to keep the PK ratio a bit higher on this specific plant.
Also, Strains, not strands.