How do you tell the difference between a female and male guppy?

This is a female guppy:

http://www.aquariumfish.net/images_01/guppy_female...

Note the dark spot behind her belly. That's the mark of a pregnant guppy. yes, they do give live birth s she really would be pregnant, not just full of eggs.

If that's not what you are seeing, then you may have a disease issue in the tank.

A very fast increase in belly size could be a size of : Over feeding this one meal, in which case it will go away by morning. 2: Constipation, in which case it should go away within 24 hours. or 3: dropsy. If this is the case it will not go away and the fish will have scales sticking straight out from it's body. If that's the case I would strongly suggest you remove the fish from the tank and humanely euthanize it. There are treatments for dropsy, but they are far from 100% successful. In fact, I would say probably 50/50 in most cases. Also, the risk to your other fish is very high should the sick fish die in the tank.

Fee free to email me if I can help further

MM

Male guppies have a gonopodium for reproductive functions. This is a transformed anal fin that appears rod formed, is held practically the frame and aspects rearward in the direction of the tail. It is used for transfering sperm to the feminine. As some distance as being gray it would be an issue of age, however ladies most likely have very bland colour, so most certainly they're ladies.

ok, the easiest way is the fins. The males have the big colourful fins females dont.

Guppies also dont have eggs. they pop out lil fry already swimming. but your right about the 100!!

have a look at the huge belly for the gavid spot. that is a dark black colour behind the back fin. the females have it. The males don't.

well it is really easy to tell which one is a male and a female a female usually will have a different type of fin than the male by their but hole( not trying to be rude or inapropriate) the female will have a sort of pizza slice shape while the males will be straight another way to find out is see if the female has a black spot on her stomach

Dont worry about having hundreds of fish because the larger fish will eat the fry as soon as the "pop" out.

A Female Has a small not colorful tail and the males have big colorful tails

Male guppies are more colorful and have a larger anal fin. Females are larger and have more rounded bodies.

http://www.fishprofiles.com/files/profiles/562.htm

simple if u want know u guppy f or m u just a naked and showing him if u guppy a round and bring to u, u guppy is man. hehehe.

Here is a site that shows male and female and info about breeding

http://images.search.yahoo.com/search/images/view?...

http://www.fishforever.co.uk/livebearers.html

Check out these sites, they are pretty good

Good luck

Any more questions feel free to email me