There are guppies and mollies.
It's a fish.
Swordtail is not a mammal, it's a fish although it gives birth. Another example like Swordtail is Guppy. Guppy gives birth but it's a fish.
A Swordtail is a type of fish that has a sword shape on their tail. Males have them but females don't.
Tropical fish flakes
sharks
Swordfish, swordtail
yes it is....it is very popular for freshwater aquariums
A swordtail is a tropical fish and a goldfish is not. The swordtail would need a higher temp. than the goldfish. Depending on where you live it probably wouldn't survive the winter.
When they start having offspring.
At about 6-7 months old
no it will not but it would attack if it or it's babies are threatened
Guppies, mollies, swordtail fish, four-eyed fish, and platies or moonfish. There might be more though.