it will have a fan tail by the begining of its tail, they are generally bigger than a male and males have alot more color than a female.
A female guppy has a darker brown line that is visible through its body. The male has a very light brown line.
The Gravid female will have the dark "gravid spot" in front of her vent. I can however assure you that if there has been a male in the same tank with a female guppy for any reasonable length of time she will be gravid.
The female guppy will develop a dark spot on the side of her belly during pregnancy. As the pregnancy progresses, the spot will grow darker.
It might want to mate with it.
All that is needed is a male guppy in with her.
yes there are. that is how they get mates.
The female guppy will be very large and will have a gravid spot near her anus. But when she is ready to give birth she will be very still and huddling near the heater in your tank.
Mosquito fish dont have any color, they are mainly tan or grey in color, and they are thinner and longer looking.
That does not happen with guppies. They stay the same sex for life.
Your male guppy is female and with child.
If the fish has a "GONOPODIUM" it is definitely a male.
About 4 weeks.