Animal Stories - Swordtail Fish

Animal-World Information about: Swordtail Fish

The most popular aquarium fish next to the Guppy is most certainly the Swordtail!
Latest Animal Stories
Mukman - 2010-07-11
Hi..I've got 2 questions..
(1)Do some female swordtails have a small "sword" at the end o their tails.
(2)I have 5 swordtails, 2 red males, 2 red females and a black and white dotted male. I got to know that swordtails are peaceful fish. But my swordtails ripped the tail off 1 of my male guppy, almost killed my goldfishes and attack all my other fishes except my betta. Can you tell me why?

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  • Ian chow - 2011-01-24
    Females do have swords and develop a gonopodium when they reach their full lifespan however. They never truly change sex.
  • CJ - 2011-04-02
    Females do not develop gonopodiums. It's possible that what you thought were females are actually males that developped late. If it remains just a very small point then its probably a female but if it keeps growing you have males my friend. The same thing happened to me.
  • Anonymous - 2011-07-21
    Your 2nd question is the one I can answer: IT'S BECAUSE YOU have more males and when that happends your male swordtails will display aggresion to other fishes in your tank to show dominance. Try ading 2 or more females in your tank.
  • Anonymous - 2011-07-21
    Oh my first reply was not correct. It's suppose to be more male than female. I typed it wrong.
lulu - 2008-11-10
Can someone help me? Both of my swordtails are sitting at the bottom of the tank and will only move if I hit the tank. At first they wouldn't stop moving and now I don't know what's going on. Oh, and the rest of the fish are perfectly fine. If there's anyone with an answer, please comment back.

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  • victoria - 2010-03-14
    I think you should check if they are spawning because female sword tails like to be really lazy when pregnant because they get really fat and weigh more when pregnant so they just sit around but
    still eat. But if they are not eating I could find out the problem.

    Just comment me.
  • Paul R. Pedigo - 2010-07-10
    Lulu, it's been my experience with them that they like to hang out at the bottom of the tank and school there. I have a ten gal. with a hybrid female swordtail, two female marigolds, and one male marigold along with a otto cat and four zebra danios. My swordtails like to hang out near the bottom in the plants. Hope this helps you out.
  • Mary Fernengel - 2011-05-25
    I woke up this morning and can't find my female red velvet swordtail fish. The male is sitting at the bottom and wouldn't come up to eat.
Larry - 2009-11-08
Me and my gf are starting to breed various swordtails... before I do I had a couple questions before I proceed.

1.) is highfin and sailfin the same as I heard both talked about as very good looking
2.) Lyretail males can not reproduce, is that correct? (so I can go about it from the female side)
3.) black tails ie bluewagtail is that really cancer and probably a bad idea to try to do?
4.) cause I was thinkin a highfin lyretail with the blue black coloringw ould be, well amazing so is that a possibility for a healthy fish

anyone know those answers?

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  • Byron - 2010-06-19
    1. a high fin or hi fin and sail fin (the term sail fin is mostly used on platies) are the same but variation is known to exist between sexes I have noticed females with hi fins keep their fins on top and not folded while on males because it is more elongated it flows down to their side. 2. lyertails cannot reproduce since it gets in the way of reproduction 3. no answer because I've seen blue wag platies only, I've never seen one with a sword but the platy I did see did not have cancer 4. As for your goal let us know how it goes I'm always interested to see how people create hi fins keep a good log on your progress
  • Melson - 2010-09-27
    Highfin and sailfin are two different breeds. Any male who's got a long fin at the the sword...cannot breed. They look beautiful but they are duds.
  • Tha IGz - 2010-10-10
    Lyretails can breed with female fancy tail guppies..I have a tank full of them and are quite beautiful.
  • anthony - 2011-04-05
    1.) Sailfin and hifin are one in the same. In the aquarium world there is many different trade names both for swordtail varieties - as such what one may perceive as say a brick red one might just say red or "orange" meanwhile it is indeed brick red. As such the sail-fin or hi-fin are one in the same just one person calls it sail fin where as the professional breeders call it hi-fin..well simpson hi-fin. 2.) Lyretail males are incapable to breed due to their overly long gonopodium obtain lyre tailed offspring mate a lyre tail FEMALE to a NORMAL finned male..50% of the offspring will be lyretails. Just remember that when lyretail offspring are born right away they don't have the lyre fins till about 3 weeks old so keep all fry till at least 3 weeks old to determine how many lyres you got. Also remember that swords are not sexually mature till about 8 months of age up till then they all look like females. One reliable way to sex the fry around the 3 month mark is to look for the gravid spot, these are females as only females have it..provided the fish variety isn't a dark for the thickening leading edge to the anal fins around 4-6 month mark these are males as this will later be the gonopodium. 3.) Any wagtail variety is not melanomic, it's only melanomic if the black is on the body the more black the higher the chance of the fish getting it. Painted swords and black swordtails are the worst color varieties for developing the melanoma but not EVERY fish gets it, it's not infectious to other fishes and certainly not to man! 4.) Yes that would be an interesting color combo to take a few yrs to develop but if you succeed then I would certainly look to have the variety registered. A good way to start if you want a blue wag lyretail is to have a lyre female sword preferably green wild color. Mate her to a male blue wag platy. That way you have 50% lyretail hybrids, mate any that resemble the blue wag male back to the lyretail swordtail to create an almost pure swordtail once again and you have an almost pure blue wag lyre tail sword created from a similar closely related species. Remember swordtails and platies as well as swordtails and variatus platys easily crossbreed. (But always if you chose to mate variatus into swords you have to use a male variatus to a female sword..male swords have been proven not to inseminate variatus females BUT if you use a variatus male to a sword female then they will cross breed. It's a good way to end up with colors no one seen before and the male fry from that cross when raised to maturity develop cool little swords that are tiny and curved up like a hook lol very neat to see.
fish gal 1 - 2011-02-02
Hi I just finished establishing bio filtration with 1 female sword tail, I added a male flame dwarf gourami and she keeps biting them. If I add more swordtails will she calm down , or will they just join in and hurt the gouramis?
Also if I add more gouramis will she back off?

I was thinking of breeding her but now I'm not sure will she just become more aggressive?

btw I have them in a 24 gal tank.

Jessica Hruschak - 2010-06-20
I have 2 female swordtails, I got them from a pet store, one was pregnant and so far I have only seen 1 baby fish... Did it eat the others? Do they give live birth all at once or every few days until the babies are ready? o_o I've already put the baby in a separate place away from the mother..

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  • Rahim - 2010-10-03
    It's a good thing you put the baby in a separate...
    This morning my S.T fish gave birth to a total of 9 babies this was every 10 minute, while giving birth she then started hunting them and eating them, I managed to save 6 of them and separated them.
    The Female Sword tail looked hungry but would not eat flakes so I fed her blood worms, and she just kept on eating and eating.
Stevie J - 2010-01-30
The white film could be Ick.
Female's get EXTREMELY stressed when carrying fry and if they are the only Female for the Male, even once pregnant, he will literally chase her to death by still trying to mate. I have found Platy's to be the worst for this situation and the 3 Females I had got pregnant, and then stressed out and died from what looked to be Ick (white film anywhere on the body, particularly fins and mouth)Two of my female Swordtails have also died from this same stress.
Other fish such as Gourami's will notice the change in the Females Biological Structure (having fry inside does create a different smell in the breeds)and will also chase the pregnant female knowing she has 'food' in the fry.
I have a female platty and swordtail now pregnant, no ick, I treated the water with an Ick treatment BEFORE they got pregnant, not during.

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  • Chris - 2010-02-17
    This also happened to one of my female Swordtail... I was looking all over to try and find out what was wrong with her. I presume you can purchase Ick treatment from most aquariam fish stores.
  • Sean - 2010-05-24
    Ick shows as small white spots that are easily mistaken for as bubbles. I made this mistake and lost two lovely clown loaches, which are extremely prone to the ick parasite. Closely monitor the spots to see if they change to determine whether or not they are bubbles or cysts. Ick cannot survive in water above 83 degrees Fahrenheit, coppertone is my choice for parasite treatment of most varieties but a white film sounds like velvet disease. What should you do...GET COPPERTONE!
  • Paul Pedigo - 2010-07-07
    Ick usually is white cysts along the sides and the fins of multiple species of fish. The most prone to ick is the black moor goldfish. I personally use Ick Away from wardley. It works wonders if you need to eradicate ick. White film sounds like velvet to me. But velvet usually uses the same color as the fish.
Christopher Ashby - 2010-04-19
Hi was wondering how to tell that my female is pregnant?

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  • Caitlin Perello - 2010-06-02
    If your female swordfish is coming straight toward you (be patient, it eventually will), and it looks pregnant at that time, then it is probably pregnant. A black spot in its abdomen doesn't actually mean anything; it can't be the babies' eyes because there are many babies at once, not just a few.
  • Paul Pedigo - 2010-07-07
    Christopher, a female that is pregnant is really FAT and will have a black spot near her anal fin. Hope this helps.
Paige Felbaum - 2004-04-06
I think this is a very wonderful fish. They come in all different colors and will breed easily. But if you are like me and breed your fish these are a good fish to start on. The fry are kind of hard to take care of but if you know how to do it they will probably live. They are very easy to take care of and live a while. My oldest one is almost 7 months now in a heated aquarium around 75 F and fed twice a day. He lives with a mollie, african dwarf frog, female guppy, tiger barb, red platy and 5 jumbo neon tetras.(in a 10 gallon tank)

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  • Debbie - 2010-03-16
    My female swordtails tail had a white spot on it she was pregnant, after she had the babies it went away and she is doing fine I use bottled spring water.. but I have a hard time having the babies live... they die on me. I have them in a separate little tank and feed them the flake food... how do I take care of the babies and keep them living so I can breed them?
  • Caitlin Perello - 2010-06-02
    I think you might want to get a bigger tank for all of those, especially with a frog in there. In my ten-gallon tank, I have a pair of swordtails (the female I believe to be pregnant), and my marble angelfish.
jj - 2010-01-22
I have that same problem of white lips on my platy but it never dies. Triple sulfa seems to work so far but I have not yet completed the treatment.

ROD DALE - 2010-01-19
I have a 29 gal aquarium and have been trying to raise red wag swordtails along with guppies, placo, cory, and neon tetras. Every time I get a female swordtail, she will have her babies, get a white coating around her mouth then die within a day of the white stuff on her mouth. I've had my water tested and it has tested a Ph of 7.2, nitrate of 20 which is normal range. I have no other problem with any other of my fish getting this white coating & dying. Does anyone have any idea what is going on in my tank? Thank you for any responce