Increasing Temperature

So i've seen a lot of people suggest increasing the temperature when the discus is not eating. What is the reasoning behind this? Does it really work?
From my experience once you raise the water temperature(86 and above) the water fouls faster. Wouldn't that make the fish sicker?

Increasing heat encourages bacterial growth (not good if your fish has an infection) but can also stimulate appetite and immune response.

you must know what a fish is up to, a good diagnosis is a good start

Increasing temperature increases metabolism and hunger, but it also (at higher temperatures like 36C) places significant pressure on parasites, viruses etc. It is just like you getting a fever when sick to raise your temperature to a level that kills the virus. It usually works well if you keep the temperature up for around 5-7 days.

Thanks all. I was just curious if there were other benefits other than increasing appetite and such