Video has been archived and can't be viewed.
Need pictures and video that are in focus and clearly show the issue.
Check the water quality for ammonia, nitrite, nitrate and pH. Post results in numbers here.
Tell us about the tank, how long its been set up, filter type and maintenance, water changes, etc.
How long have you had the fish?
Have you added anything to the tank in the 2 weeks before this started?