How Can I Tell?

[justinday13]

I have two guppies that seem to be following each other everywhere in my tank. They won't go anywhere without each other, and are always chasing each other around. I'm not sure if either is male or female, but one's belly is kinda black....just wondering if there's anyway to tell if one is pregnant.

Thanks

 

[juliethegr8t]

First I'd suggest you figure out if you have a male and female. Males are much brighter in color with fancy patterns and longer tails. Females are usually (though not always), quite a bit plainer - duller colors. If one is pregnant, you should be able to tell - they get obviously large and develop a gravid spot, which may be the black you're talking about. It's a dark spot on the belly, behind the fins.

 

[guppymonkey]

The other way to tell the difference between males and females in livebearers (including guppies) is to look at the anal fin. The anal fin is the one on the bottom right around where they poop. The males have a long pointed fin (called the gonopodium) that is used to insert the sperm into the female (just like in humans). The way to tell if the female is pregnant is if she is fat. Non-pregnant females are just as slim as male guppies but they balloon up quickly when they become pregnant.

 

[snowyangel]

As said by julie, the females with have a gravid spot(dark spot near the anal fin), have large round stomach's, and have a dull body colour . The males body is thinner and display much brighter colours, with often bigger, fuller tails.
To tell if she's pregnant is most often determined by a gravid spot. Her gravid spot will grow large and darken as the eggs develop. Closer to delivery time, the spot will be nearly black. I've heard that the darkness comes from the fry's eyes, but i dont really know.
Here's my guppies(kind of dark pics but u can def' tell my male guppy from my female):
http/fish.orbust.net/forums/index.php?sh...showtopic=17075

If you still can't tell here's a link to two male guppies chasing a female:
http/www.petfish.net/guppies1.jpg

And this link shows a female with a dark gravid spot:
http/www.aquariumfish.net/images_01/gupp...fem_pd_w180.jpg

Hope I've helped