Molly Fish Care Tips:
Tank Size: Mollies need a minimum of 20 gallon size aquarium so that they can swim around constantly utilizing the entire aquarium space.
Tank Setup: Add lots of artificial or live plants in your tank. Mollies like to have lots of hiding places in the tank.
Number of Fish: Keep at least 2 or 3 female mollies for each male else you can keep all females. This is because the male mollies are hyperactive and constantly chase the female mollies.
Water Filtration: A simple foam filter or a hang on the back filter will do. Mollies like to swim around the surface of water in search of food, avoid using filters that disrupt the water surface.
Water pH level: The water pH can be between 6.5 to 8 i.e. moderately hard to very hard.
Water Temperature: Molly fish are tropical fish, which means we need an aquarium heater. The water temperature should be between 72 to 84 F (22 to 29 C).
Food: Mollies are omnivores and in the wild they feed on small invertebrates, algae and plant matter. In the tank their favorite frozen foods are bloodworms, daphnia, and brine shrimp. You can also feed them any good quality flake food.
Tank Mates & Other fish: Mollies are a popular community fish but you need to keep an eye on them if you combine them with other fish that have long flowing fins. They tend to nip such fish. Also, fish substantially smaller than molly shouldnt be kept together as they tend to chase them and try to eat them if they can. The best tankmates for Mollies are other livebearers like Platys, Swordtails etc.
References:
http://www.wikihow.com/Take-Care-of-Molly-Fry
http://freshwaterfishfacts.weebly.com/molly-fish.html
http://www.myaquariumclub.com/an-in-depth-look-at-molly-fish-1524.html