Guppies mature differently depending mostly on tank water parameters. For example a colder tank will slow the maturation of your guppies but will probably also extend their lifespan. When your males start to colour up-they are most likely ready to reproduce, this should be in the 2nd or 3rd month. Females will be ready at this point too. Your males will be approx. 2 centimetres long, females a little bigger.
Only guppies breed with guppies naturally.
I doubt that they can breed, a lot more depends on if two fish can breed than just their size, as far as I know guppies can only breed with other guppies.
Don't own female guppies if you don't want youngsters.
id say guppies, they breed like rabbits
no chance they find their own companion and breed this can be done only scientifically at laboratory levels
guppies there like rabbits and bettas are very hard to breed
They are livebearers and breed like guppies.
depends on the age, breed and what it is fed
The size of a horse all depends on age & breed.
As do all other animals, guppies breed, unless the female has been purchased from a pet store that used sterilization chemicals on it to sterilize it and to change the color to "make it more attractive".
no cories cant interbreed with any of those fish. bronze cories breed with bronze cories
I'm not sure but some people say you should or the baby guppies will breed.