Platies are one of the most common fish recommended for beginning hobbyists due to their hardiness and prolific breeding. There are many domesticated strains available displaying many beautiful colors. Perhaps their only drawback is that they are capable of overpopulating a tank due to their rapid reproductive rates. Males are smaller and slimmer than females, and possess the modified anal fin gonopodium used in passing sperm to the female. Females are capable of storing sperm and giving birth to live fry long after being separated from males.
Platies are great beginner fish as previously stated. There are 2 downfalls to having them. 1. They reproduce a LOT 2. They eat a lot. Just make sure not to over feed them because they will keep eating and always act hungry. They are funny little guys though, fun fish to have.
I've just finished cycling my new 30 gallon and I'm doing well with my zebra danios. I'd like to add platies, but I keep hearing they need salt. I'm afraid salt would mean death for my plants, so I'm not keen on adding it... do they REALLY need salt?
platies don't need salt although they a are type of fish with a weaker immune system, so some brackish-freshwater aquarium salt is always good, and don't worry about your plants, as low levels of salt don't hurt. DON'T USE TABLE/ SEA SALT because it is NOT meant for fish