Is she pregnant or just big?

[lindsayf1387]

So I’m pretty sure this is a female platy but just needing an extra pair of eyes to see if she’s pregnant or just a big fish.

 

[Colin_T]

Is it a balloon platy?
Balloon platies have a shorted body than a normal platy and this can make them fatter due to their organs being squished up more.

It's definitely fat, but is probably gravid (pregnant).