purple stems??why?

a few of the stems on the leaves are looking kind of purple/red.
why?
also
i dont have a humidity monitor neither and have no idea how humid it is or isnt
i grow in a tiny closet space,one plant. how can i add humidity to the room .
i spray water here and there but i feel it dosnt rlly do much ,
any help will be well appreciated

You need to get a humidity monitor otherwise you'll have no clue what the humidity is, one easy way of upping the humidity is putting a cup of water in direct light so that it slowly evaporates but I wouldn't suggest messing with your humidity until you can see what your doing that just sounds like a disaster waiting to happen like if you tried using pH up and down without know what the pH you had to begin with was, too much humidity will attract mould and insects and stuff so you definitely want to keep it under control. And with the stems I don't really know exactly why, from what I understand a number of things can cause it like certain deficiencies and also if your temps aren't stable it can happen when its too cold or something. Anyway good luck!

are you using r/o or distilled water? what are the temps of your room?

alot of my stems are purple as well, it can be just genetics. any pics? does it look like this?

Mag deficiency

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