How do you tell if a guppy fry fish is female or male?

It's tough to determine the sex of guppy fry (baby guppies) until they mature, typically at around 3-4 months old. Here's why:

* They're too small: Fry are tiny and don't yet develop the visual cues used to tell genders apart.

* Gonopodium: The most reliable way to tell a male guppy is by the presence of a gonopodium (modified anal fin used for mating). This develops gradually, and you won't be able to see it in fry.

However, there are some hints you can look for, but these are NOT reliable:

* Color: Male guppies tend to be more brightly colored, even as fry. But some females can also have vibrant colors.

* Body Shape: Males tend to be more slender and torpedo-shaped, but this is subtle in fry.

The best way to determine sex:

* Wait it out: Patience is key! As your guppies grow, you'll see the gonopodium develop in males. It will look like a long, thin, pointed fin.

Remember: Even with these hints, it's not a sure thing until the gonopodium is clearly visible.