PLEASE HELP ! ASAP . Sick guppy :(

[freshwaterfins]

About a week ago I added 3 new guppy’s to my 5 gallon tank making a total of 4. I had more before but all of them died before hand so after waiting a couple weeks to see if the last one was okay i added more. I woke up to find one of my guppies on the floor with faded colors , clamped fins , and an arched back. Once he saw me he swam up to the top and is trying to swim with other fish but he just lays at the top and the other fish try to nudge him and push him around please help. The water temperature is 82 degrees Fahrenheit.

 

[firefly1152]

Seems a little warm. Do you have any water movement or air stones?
Also, is the tank cycled?

 

[Autumnsky]

What size is your tank and filter?

I would do a pwc asap.

How often do you do water changes and how much?