|Scientific Name||Xiphophorus hellerii|
|Minimum Water Size||20+ gallons (75.70+ liters)|
|Ease Of Care||Easy|
|Average Lifespan||3-4 years|
|Approximate Adult Size||4 inches (10.16 centimeters)|
|Water Parameters||64-82 degrees Fahrenheit (17.77-27.77 degrees Celsius), 12-30 KH, 7.0-8.3 pH|
|Native Region||North American to Central America|
Originating from North American all the way down to Central America, the swordtail is a fish that is slightly bigger than the molly for being a livebearer. Swordtails are one of the many fish that are extremely ease to look after as they require no special care what so ever. Due to their popularity and unique trait of their tail having a sword-like appearence, there are several different colorations and patterns that are sold around the world. Such colorations and patterns include but are not limited the hifin variations, marigold wag, koi patterns, some that have been bred to have a sword not only on their bottom tain portion but also on their top portion, and lastly even some that have been crossbred with their close family member the platy. Many common swordtails that are sold around the world have been at one point in time bred with a platy (either accidentally or on purpose) in order to increase the swordtail's size and/or to change the finage that they have.
Although swordtails in general are not classified to be schooling or shoaling fish, they do take great kindness towards other swordtails if they are present in the same water. Male swordtails however will require a minimum of at least 3 female swordtails in order to be happy, otherwise he will start to bully and try to mate with any other fish that is of moderate size. Getting multiple males will only create a more stressful situation for all of the fish, as they will constantly be trying to mate with each other and establish a strict hierarchy throughout their lifetime.
All swordtails are classified as being livebearers, which means that they give birth to living fry compared to others which will release eggs into the water column. In order to tell genders, we can look at the anal fin of this fish. All males will have a tube like fin (called a gonopodium), where as the female will have a more round fin along with a pregnancy spot near this fin. It is to be noted however, that it can be almost impossible to tell the gender if the fish has not reached full maturity yet since these various signs will not be fully present or easy to tell apart. Due to their various colorations and finages, it might be very hard to tell if the anal fin is actually just a fin or a gonopodium. Sadly, due to some breeding conditions in order to make their fins longer, more vibrant, or to increase their sword-like tail many males are actually born sterile and/or will have a gonopodium that is formed incorrectly.
The male swordtail will mate with any given female swordtail or platy within the same water, pregnant or not, and will release a type of sperm into the female. Shockingly, the female can hold a male's sperm for multiple months and is known to get pregnant, and release fry for up to 6 months without the help or addition of any males in the same water. The average gestation period for a female swordtail is anywhere between 28-34 days which is mostly dependent on the diet provided to the mother during the pregnancy. Once the fry have been released by the mother, there will be no parental care provided from either the father or mother. In most cases, the mother will eat the fry right after they have been born or shortly after.
In order to see the best coloration of any swordtail, it is suggest that you give them a varied diet which is mostly based upon algae, then a plant based food (mostly what flakes are made of), and then slightly a meaty food such as pellets or live foods. During a female's pregnancy, algae will help with increasing numbers of fry being produced along with a more stable health throughout their first few months.