Sick Guppy

[TheSims3Dude]

I have a guppy, lol, I guess you can tell from my post, anyways, yesterday she was looking sick, her scales (bottom scales) were sticking out a little,
so I though perhaps she was getting dropsy, but... I just checked on her right now, and she's extremely skinny, and she's not moving very much, does anyone know what I can do to help her? I feel aweful right now

 

[WILDER]

Size of tank in gallons or litres.
How many fish and which type.
Water stats in ammonia, nitrite, nitrate, and ph.

Lifted scales can mean knocked them on something in the tank, injury, fighting, dropsy, parasites beneath the scales.

Has the guppy lost weight due to not eating.
Does the guppy look bloated.
Check the anus of the fish to see if it looks enlarged or red and inflamed.
What does it look like when the fish goes to the toilet.
Is the stomach sunken in.
Is the spine bending.
Any signs of flicking and rubbing.
Excess mucas on gills or body of fish.
Erratic swimming or darting.
Laboured breathing or gaspings.
Can you see anything beneath the scales.