Camel Guppy

[Guppy Mama]

I am in need of knowing what causes this.

A female guppy, who usually had no deformity at all, suddenly has a big hump. It's not like those fry who have the hook in their spine. It looks like a big camel hump. I am assuming it is fluid, because her spine is straight. She is pregnant, but not about to burst.

Is she ok?

 

[Guppy Mama]

...as an update, her big camel-like hump has largely reabsorbed. She has not given birth yet, so I doubt it was pregnancy realted. I am stumped.