I am not sure if one of my frogs is stressed or not. They have been swimming around at a near constant rate and have not rested. I would think it would be tank conditions, but the tankmate has been very relaxed.

My positive guess is that she is a rapidly growing frog and may be trying to shed some skin.
My negative guess is that she has not enough hiding space.

Here is a video to show you what I mean:
Instagram

Also the video is a little tinited. She doesn't look that pink in real life.