Sick Discus - Need Help

[Aquadaft]

Hi,

My Discus has suddenly taken ill. It was healthy and spawning a week back and has been continuously spawning for months now.

Symptoms :

Body color has turned black - Its a blue turquoise
Barely able to swim around, lays at the bottom of the tank, moves around, swims in circular motion, sometimes violently


Its right now quarantined and in an Epsom bath.
I have a video that I am not able to upload because of the size.

20190122_143925.jpg

Please advise on what medication is suggested. I am not sure what it is.

Thanks in advance