Originating from the Amazon Basin in Brazil, the Molly Fish is popular with aquarists from beginners right through to advanced. They are a peaceful fish, but can show signs of aggression if they are surrounded by aggressive tank mates. They should be kept in groups of four, which should be mainly made up of females as males are known to harass them.
Make sure you provide a suitable cover for your aquarium, as the Molly is known to be a jumper.