Is My Swordtail Fish Fat Or Pregnant?

Is My Swordtail Fish Fat Or Pregnant?

Swordtail fish are among the popular choice of aquarium fish among hobbyists. Their unique appearance (sword-like tail) and peaceful temperament have helped them become widely accepted pet fish around the globe. But, it doesn’t mean that swordtail fish are without any problems. They are sensitive like most fish and suffer from obesity. So, it’s worrying to see your swordtail fish getting fat. How did they get fat? Did I overfeed them? Or,  is my swordtail pregnant? Such questions are never-ending. So, Is your swordtail fish fat or pregnant?

Swordtail fish become fat mostly when pregnant, associated with a gravid spot and change in behavior like aggression and nesting. However, Swordtail fish also become fat due to dropsy infection, tumor, bad water conditions, constipation, overfeeding, and as such.

If you feel like your swordtail is getting fat, it’s time for action. First, you should try to diagnose why your swordtail fish appears fat. Pregnancy is the most common cause, followed by dropsy, infections, overfeeding, etc.

This blog post will discuss how to distinguish a pregnant swordtail fish from a fat one. I’ll also give you suggestions on the treatment of dropsy infections and how you can solve overfeeding. Now, shall we start?

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What Makes Your Swordtail Fish Appear Fat And Bloated?

Just remember that when your swordtail fish appears fat or bloated, it isn’t a normal condition for their body. And, there are many reasons why your swordtail fish appears fat. Some of them are:

Dropsy

Dropsy is when your swordtail fish retains fluid inside the body. This causes a swollen belly. The swollen belly drops down. Hence the name dropsy.

When you have bad water conditions in your tank, your swordtail fish has lowered immune system. As a result, many bacteria will cause infections resulting in dropsy.

To diagnose dropsy, you have to check whether they have bulging eyes, pale gills, and their scales stick out along with a swollen belly. Moreover, your swordtail fish will be lethargic, inactive, and weak when it has dropsy.

Indigestion/Constipation

When you feed your pet with dry, protein-rich food, the food may be stuck inside their intestines. And since the poop can’t come out, it accumulates inside their body which swells their belly. It is quite common for your swordtail fish to be constipated because swordtail fish eat a lot.

A swordtail fish with constipation has long, stringy wastes floating from its back.

Weight Gain Due To Overfeeding

Out of love, you may end up overfeeding your swordtail fish. And, since swordtail fish are food-lovers, they end up consuming everything you feed them.

An overfed swordtail fish is not at risk for ill health, dropsy, infections, etc. Their color is normal, their appetite is good, and they’re quite active too. It’s just that they’re fat just because you overfed them. Too much overfeeding is bad because it may constipate your pet which is bad for their health.

Tumor

A tumor of the abdomen will make your swordtail fish’s belly appear fat and bloated.

Only a particular portion of the abdomen or whole abdomen appears fat. At the same time, the best part of the body or some parts of the abdomen is normal. Swordtail fish suffer from benign and harmless tumors. But, most of the time, swordtail fish die from malignant tumors which spreads throughout their body.

The cause of the tumor might be retrovirus or due to poor water conditions in your tank.

Pregnant Swordtail Fish

Even if your swordtail fish has just recently given birth, don’t ever think that your swordtail may not be pregnant once again. Swordtail fish are effective breeders who can get pregnant every month.

In addition, a female swordtail can store sperm in her pouch for many months. And, the females can get impregnated multiple times even without the presence of a male swordtail fish. So, your female swordtail fish gets pregnant every 28 days, even without a male swordtail fish’s help.

I’m saying this because if your female swordtail fish is bloated, chances are, she is most probably pregnant.

The pregnant female swordtail fish will be fat because she stores the fertilized eggs inside her belly. All the fry develops inside her. And no, swordtail fish don’t lay eggs. Swordtail fish are livebearers and grow the fry inside their belly and give birth to live fry once it is fully matured.

How Will You Differentiate Whether Your Swordtail Is Fat Or Pregnant? [Signs Of Pregnancy]

When you see your swordtail fish bloat, it is not quite obvious, as a fish owner, to find out whether it is because of dropsy, infections, overfeeding, or just because she is pregnant.

But, worry not, for I am here for the rescue. I’ve listed signs of pregnancy below so you can easily know if your swordtail is pregnant.

Check Gender

Firstly, you need to check the gender of your swordtail fish. And to differentiate the gender, you need to check their caudal fins. Only male swordtail has the sword-like protrusion. Likewise, only swordtail males have gonopodium. This is the sure-shot way of knowing the genders of swordtail fish.

This is necessary because only female swordtail fish can get pregnant. Therefore, once you have realized that your swordtail fish is a female, there is a high probability that her fatness is due to pregnancy!

If you have a fat male swordtail fish, chances are it is just fat due to overfeeding or some infections like dropsy.
Did you know? Swordtail fish can change genders. Please read all about it here.

You See Your Swordtail Fish Mating

If you have by any chance seen that the mating occurred, your swordtail fish is probably pregnant and not fat.

How do you know mating occurred? First, the male swordtail will chase the female swordtail. And then, he will erect his pointed gonopodium and inseminate the female swordtail fish. Of course, this deed is quick. But, sometimes, you may be lucky enough to see it.  You can guarantee that your swordtail is fat due to pregnancy then.

There Are Males In Tank

If you have kept a mixed swordtail tank, the males will fertilize the female swordtail fish in no time. So, there is a high chance that your fish is pregnant rather than just fat.

Belly Shape

Now, this one is important. Generally, dropsy happens all at once, and you’ll suddenly see your swordtail become fat. But, in pregnancy, the belly bulges out slowly day after day.

Perhaps the most important thing you should notice is that the pregnant belly is squared from the front rather than rounded like dropsy. Dropsy is a more balloon-like belly. Likewise, a pregnant belly will also have a dark gravid spot, which the fat belly lacks.

Gravid Spot

The gravid spot is the surest sign that your swordtail fish is pregnant. This is a dark hue spot below the abdomen which is the growing fry pressing against the uterus—the darker the hue, the further the pregnancy.

Behavior Of A Pregnant Swordtail Fish

One of the signs your swordtail fish is pregnant is it doesn’t like to eat much.

Due to hormonal changes and fry growing in her belly, she lashes out on her tank mates and other swordtail fish. So, they will behave aggressively during pregnancy.

Moreover, a pregnant swordtail fish hides behind plants, decorations, and foliage in your aquarium. Nesting happens when your swordtail fish is near their due date.

Swordtail fish also breathe rapidly when they’re near their due date. This is because the pregnant swordtail fish is holding the baby fry in her belly. It’s really tiring to have internal fertilization after all!

How To Treat Bloating And Fat In Your Swordtail Fish?

After you’ve diagnosed the cause of your swordtail fish’s fat belly, you should get into their treatment immediately, especially if they’re fat due to tumors, dropsy, constipation, and overfeeding.

It would help if you cared for pregnant swordtail fish, too, because pregnancy is the time when a swordtail fish is the most vulnerable.

Maintain Tank Condition

A bad tank is your swordtail fish’s biggest nightmare. Ammonia and nitrogen spikes, extreme pH, too cold or hot water, and so on will compromise your swordtail fish’s immune system.

Always change the water (around 25%) every week, even when you have a filter on.  Swordtail fish need a filter, but they can live without one. However, without a filter, you need to change water almost every day or every alternate day.

Moreover, try to balance the water pH and temperature. The temperature can be maintained with a heater and checked with a thermometer.

Remember one thing. Prevention is better than cure. And to have a tank with optimum conditions is better than having a tank with bad water conditions and diseased swordtail fish.

Treat Dropsy And Infections

You neglected your swordtail fish and didn’t balance your water parameters. And, your swordtail fish are already infected. So now, what should you do?

Well, firstly, manage a quarantine tank. This is where you keep all your diseased fish so that these diseased ones don’t spread the infection to others. Yes, dropsy is an infectious disease. And it would help if you separated the fish with dropsy from those not yet infected.

You should add one teaspoon of aquarium salt/gallon of water to the tank in the quarantine tank. This salt is used as anti-parasitic and kills all microbes in your swordtail’s body.

Moreover, you can use antibiotics to treat dropsy too. You may want to consult with your vet about the antibiotic you should use!

Provide your swordtail fish with a high-quality diet. And monitor your swordtail fish regularly. Sometimes, dropsy can go away if you treat the underlying condition like a parasitic infection.

But, most fish owners prefer euthanizing their swordtail fish. And that’s because dropsy is infectious and hard to treat!

Treat Constipation

To treat constipation in your swordtail fish, provide them with boiled and peeled pea. Peas have fiber, so they’ll help your swordtail for easy excretion of poop.

Moreover, some people treat their constipated swordtail fish with Epsom salt. Epsom salt is believed to have a relaxing effect on intestinal muscles.

Avoid Overfeeding Your Fat Swordtail

When you overfeed your swordtail fish out of love, your food-loving swordtail fish will become fat in no time. That’s why to feed your swordtail only twice a day and that too in, little amount.

See, you might think it’ll be cruel to underfeed your pet. But, actually, research has proven that fasting is beneficial for a swordtail fish. And, underfeeding is actually better than overfeeding.

Try giving your swordtail fish only what they can eat under 2 minutes during each feeding session. If any food remains at the end of two minutes, scoop out the food with a net. Too much food can go wasted, too, which might foul your tank.

It would help if you fed your swordtail twice a day.

I recommend that you provide a fibrous and varied diet for your swordtail fish. For example, a meaty diet like meat, daphnia, brine shrimp one day, and veggies like carrots, zucchini, pea the next. I’m sure your swordtail fish will be excited to try varieties of food full of nutrients.

FAQ

How Long Are Swordtail Fish Pregnant For?

The gestation of swordtail fish is for an average of 28 days. But, the delivery of fry may be as early as 25 days to as late as 35 days or more. The delay in pregnancy happens due to bad water conditions, stress, immature fry, and poor health of the pregnant swordtail fish.

Do Pregnant Swordtail Fish Die After Giving Birth?

If you constantly breed your swordtail fish, it will compromise their health, especially if they are really young. But, no, swordtail fish don’t die after birth as they are quite hardy fish.

Conclusion

So, I hope you got the answer to your question of whether your swordtail fish is fat or pregnant. Once you rule out the signs of pregnancy, you can easily understand that your pet is fat due to other causes like dropsy, infections, tumor, constipation, or overfeeding. And once you control their diet and shrink back to their normal size, you can understand that your swordtail was fat because you overfed them.

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