Neon Tetras have ich, treating 55 gallon?

[MC1973]

What's the best treatment for this ich problem? Only my neon tetras have it, but i'm pretty sure my other fish will get it soon enough.

I have a rainbow shark
tiger barbs
and some corydoras

Do I need to medicate the entire 55 gallons? What medication do I use for this? I might also need to do the same for my betta.
How do I remove the medication after? Do I need to remove it?

 

[MC1973]

Also I have a pleco...

 

[dkpate]

You can slowly raise the temp to 86*F, and leave for at least 10 days.