Hello, I purchased a calathea not long ago and read that it can be placed in a low-light area. I've done more reading and now know that it needs filtered light so I've moved it in front of my east facing window. The stems have gone extremely limp because I had it in a dark area for a while, also that room tends to be colder. I've pulled the plant out of its pot to check for root rot however I'm not sure what that actually looks like. Some of the roots looked black so I cut them off and put the plant back into its terracotta pot. I've used a chunky potting mix so I think I've got the soil choice right. Could this be happening because my pot is too big?
Also one leaf has turned yellow. I think this is because of over watering but i am trying my best to keep the soil moist and not wet. Also some leaves have dark brown dried edges... I took some photos of the roots in hopes that someone will be able to know if my plant does have root rot or not. Also I've propped up the stems because they are so limp. If I am able to upload a photo of the plant, I will. Any advice would be so helpful!!