Possible Potassium problem? Please help!

Help guys I'm pretty sure my plant may have Potassium a defficiency, the branches have a red colour to them.

Could be mild stress or the strain also.

Yeah, I wish I knew the strain but it's just from bag. I also have the Blue Sage strain, which is a little redish purple but it's not nearly as much.

Soil or hydro? Do a soil test.

They are all being grown Hydroponically.