How can you tell how old the guppy fry are?

How can I tell the gender of my guppy fry?

• I have 2 guppies from a fry someone gave me, they are almost 2 monthes now, I noticed one of them is fatter/wider not the length, and other is skinnier, they both have the same type of fins and they both are silver like their mother lol so gender do u think they are? And how I can I tell? Also I don't see a gravid spot although i noticed a black spot on one of their tails' it was lighter before now its really dark, and someone there are dark spots on their heads that come and go

• Answer:

  If you are keeping guppies in your home aquarium, you must be aware by now at how often the females breed. Since a female guppy could get pregnant as often as every 30 days, there is a need for controlled breeding if you do not have the tanks to accommodate a large number of fry. If breeding is properly spaced, you could better manage and care for your guppy fry. When you notice your pregnant female guppy drops her youngsters, it would take a little work for you to help them grow and develop well. Fry tend to be eaten by the mature guppies when they’re kept in the same tank, it is then advised to separate them or utilize a breeder box, net breeder and a larger tank of about 5 to 10 gallons in size. If the adults are well fed, there is lesser chance for the fry to be eaten. However, providing the safe zones for the young ones is always advised. Caring for your fry involves determining their genders to do controlled breeding at the earliest time. Generally, guppies have a tendency to have more female offspring. Though you can’t sex guppies unless they are adults, there are a few identifiable differences between a male and a female guppy to be able to tell which is which while they’re young. Only males develop colors on their bodies and their anal fin is somewhat pointed. It is very seldom to see female guppies with bright colors such as their male counterparts. They tend to be more active than the females too and are found to chase around a lot. Females usually have grayish shade on their body, and they have rounded anal fin. In about 2 to 3 weeks, female guppies develop a gray spot (gravid spot) a little above their anal fin area. This can be better seen when you place them on a clear glass. Expert aquarists could be able to identify the spot earlier than that. A guppy does not have to be pregnant to see that dark spot on their body. Waiting for the gonopodium in males is said to be the most reliable way to identify a guppy’s gender. It is a somewhat modified fin that appears gray and horizontal. It is said to be the determining factor in the gender of guppies and other livebearer fishes as well. However, it takes a while to see that, and by that time, your female guppies may have become pregnant already and setting up a proper breeding strain may be too late already. Breeders who wish to sex them earlier develop many ways to be able to do that. They usually give the fry a good feed, some use spirulina or any brand would do, and take a close look at them when they are full. Prominent pot bellies could be observed from female guppies and males will show pot chests. Proper sex identification would mean effective breeding for your guppy. Learning how to tell the gender of a guppy fry is important if you are keeping these fishes in your tank. With a little experience, you would be able to enjoy your fishkeeping experience much better with your guppies.