Swordtail fish is one of the member of live bearer family. Others members are molly, guppy and platy. These are also live bearers and give birth to live young fry instead of eggs. These are quite famous aquarium fish just like others family members because of their ease in breeding, hardy nature and less care. Swordtail fish are tough, beautiful and good community fish. They are peaceful with other fishes of same size and form beautiful community tank. However they can eat very small fishes or new born kids even of their own kinds. These are available in various colors such as red, yellow and green. They are named as "swordtail" because shape of their tail is like sword. These are omnivorous and can live on almost any food you provide. However you must provide them protein and vitamin rich food for longer lifespan.
Differentiating between male and female swordtail fish is easy by looking at their anal fin. Female's anal fin looks like fan while of male's is like thin stick known as gonapodium. They can grow up to 4 inches and have lifespan of 4-5 years if good care is taken in terms of water conditions. Males are little bit aggressive and like to chase female. Due to which female may get stressed out and die. To prevent this you must put 3-4 females per male and lots of hiding spots in aquarium. Also provide live or fake plants in aquarium. They can easily thrive in small aquarium of capacity 10 gallons or more. Swordtails are good swimmer and are found at those places where water current is high. So you can have good water current in aquarium if wished.
Temperature : 23 - 28 degrees Celsius (72-82 Fahrenheit)
Breeding : Live Bearers, Easy
Lifespan : 4-5 years
Food : Omnivorous
Nature : moderate
Tank Size : 10 gallon or more
pH: 7-8
Care : easy
Distinguish male and female swordtail fish
The tactics to distinguish between male and female swordtail fish is same as that of other family member of same group which includes guppy , molly and platy.You must be able to distinguish between male and female so that you can put appropriate number (i.e 3-4 females per male)as male love to chase females and harass them.Also sometimes males are aggressive to other swordtail male fish .Generally males are slender in shape while the females are rounder and slightly larger then males.The females belly become thicker at the time of gestation period.Also sometimes a black spot is visible on her body know as 'gravid spot' which are eyes of babies .The most key point to distinguish is that female's anal fin looks like a fan while male's fin is well developed into tube like structure known as 'gonapodium'. .However this feature must be observed in adult swordtail fish.Male's show extension in their tail and form sword shape while female's don't.The above picture is of female while the below one is male swordtail.These pictures will give you idea to distinguish them.
Swordtail fish breeding can be easily achieved in your aquarium.These are one of those aquarium fishes which are easy for breeding same like molly fish, guppy and platy. Swordtail fish are live bearer which means instead of giving eggs they deliver young babies.The main point is that you do not need any special preparation for breeding. They will spawn under normal circumstances. Some times it happens that people buy swordtail fish and put them in their tank and after one day they found small babies swimming in tank.The aquarist are not ready for this and got tensed. At that point you need to just separate the parents and babies because after birth the mother swordtail and other fishes will eat the fry(babies).Instead of catching fry catch adult fishes as you can harm the fry by net.
Preparing for Spawning and Tank Setup
Also change 10-15% of water in 2-3 days. The male swordtail likes to harass the female for mating which may even result in the death of female. So you need to put 3-4 females per male. Also add lots of hiding places made up of drift wood, plants, gravels and marbles. So that female can hide between them and not get stressed out. After mating female will take about 4 weeks to deliver birth to fry.Swordtail attains their sexual maturity at the age of 4-5 months at this stage they gets ready for breeding.The females are thicker than the male and have fan shape anal fin while the male's anal fin looks like thin tube. You must provide them food rich in protein, live food is best option. Protein rich food will encourage them for breeding.
Spawning
When female will be about to give birth to fry you can observe slight changes in her eating and swimming habits.The belly size will increase and looks like square \____/ . At this time you can put the mother in other aquarium made for fry only, do it gently otherwise she may give birth to premature babies or will delay it. When she is done giving birth in separate aquarium move back the mother into previous one as she will eat them. She can take up to 2 hours to give birth to all babies.The number of babies may be around 40.
Fry Care
Remember the fry aquarium must be properly recycled. Also do not have any suction pump or water filer which may suck or kill the fry. You may raise fry in same aquarium with parents provided you are having large tank with lots and lots of hiding places made up of marbles, wood, large gravels, plants , spawning mobs and especially floating plants. So fry may hide in them easily. However this is risky and only few will survive.
Breeder box
Their is another option that is you can buy net breeder or breeder box which is very cheap and easily available. You can simply attach the breeder box with the walls of aquarium and swordtail fish fry will have same water and temperature condition throughout the time which is important. Breeder box have 2 compartment above and below having small spaces at interface. The pregnant mother it put on the above compartment. When she give birth to babies the babies comes into bottom compartment through small spaces in protection.
Swordtail Fry Food
You can give newly hatched brine shrimps or crushed flake food.You can also give them hard boiled egg yolk which is yellow part of egg.Form thick paste of egg yolk and put few drops of it.They require it in very small amount as they have extremely small stomach.Give them 4-5 times a day.Also if possible remove uneaten food from aquarium as it will spoil the water .But don't harm the baby at any cost.Also change the 5 -10% of water daily.Avoid fluctuation in temperature of water and don't move fry here and there.