Guppy Fish Dropsy Disease, Symptoms and Remedies

Disclosure: When you purchase something through my affiliate links, I earn a small commission. As an Amazon Associate we earn from qualifying purchases. read more

Dropsy refers to a medical condition in both humans and aquarium fish when the belly becomes bloated due to accumulation of water or fluids in the guts and other internal organs.

What is Dropsy?

Dropsy disease in fish and guppies is not very common. Fish that has dropsy diseases have a bloated belly, really round, oval shape and its scales start to protrude, forming a pine cone appearance.

The bloat can be caused by fluid buildup in the colonic cavity, polycystic kidney disease, amoebae or bacterial infection (mycobacteriosis).

Many refer to dropsy disease as bloated or swollen belly diseases.

Can Guppy Fish Recover from Dropsy?

Dropsy caused by bacteria cannot be treated. It is contagious, but usually fish with strong immune system will not get infected.

Dropsy caused by other factors such as water pollution, stress or improper nutrition can be treated.

Dropsy Diseases Causes and Symptoms

As stated above, dropsy diseases in guppy fish and other fish can be caused by various factors.

Mycobacteriosis causes dropsy in very rare cases. Fish with strong immune system will not be affected by these bacteria. Though, if the immune system of the fish is compromised, it can lead to serious infections.

The immune system of fish can be weakened by various factors:

  • Poor water quality
  • Ammonia and nitrite spikes
  • Stress due to transportation or aggressive tank mates
  • Fluctuating water temperature
  • Improper feeding

Usually a small amount of stress will not affect the immune system in such a great manner, that fish will not be able to fight dropsy or other diseases. In most cases dropsy is and other guppy fish diseases are caused by water pollution.

How to Treat Dropsy?

If dropsy is caused by bacteria, the infection can affect the fish so quickly that it can’t be cured. Expert fish keepers recommend euthanizing and disposing the infected fish in order to stop the spread of the infection to other fish.

Others say that with proper treatment, some fish can be cured of dropsy. Here is a commonly recommended treatment for dropsy:

  • Quarantine the sick fish in a “hospital tank” (bare bottom tank with a sponge filter is best)
  • Once a day do an Epson salt bath in a separate container (2 tablespoons of Epson salt per gallon)
  • Feed the sick fish with fresh, high-quality food (use good flake food)
  • Treat the hospital tank with antibiotics

It is important to quarantine sick fish in order to prevent the spread of the disease to other healthy fish. Do a 50% water change on the original tank and monitor the remaining healthy fish in order to spot any early symptoms of dropsy.

You can treat the whole tank with Epson salt, however, it is more effective to do short baths. Put one gallon of aquarium water in a separate container and add 2 tablespoons of Epson salt. Leave the fish in it for about 30-45 minutes. Put back the fish in the quarantine tank. Do this once a day.

Do not feed old fish food to your fish. If you have food that is older than 6 months, just get a new box of high-quality flake food and feed that. You can also prepare fish food at home or feed live food. Make sure you feed a variety of quality food to your guppies.

If the sick fish does not respond to the Epson salt treatment after a few days, you should use antibiotics. In most countries, antibiotics can be prescribed only by a vet. By dosing antibiotics, you will also kill the beneficial bacteria in the filter. When treating your tank with antibiotics, test for ammonia and nitrites on daily basis.

How to Prevent Dropsy?

As I always say, it is much easier to prevent guppy diseases than treat them. As with most other diseases, dropsy is caused by poor water quality, wrong feeding, dirty fish tank, stress and lack of nutrients.

Here are some tips on how to prevent dropsy in your guppy fish:

  • Do regular water changes (30% weekly)
  • Maintain tank regularly (clean filter, vacuum substrate)
  • Do not overcrowd your tank
  • Do not overfeed your fish
  • Do not feed old food to your fish
  • Feed a variety and quality food
  • Keep the water temperature stable with a heater
  • Avoid aggressive tank mates

If you feed various high nutrient food and maintain your tank regularly, keeping the water parameters stable, the chances of your guppies developing dropsy is very low.

Guppy Fish with Bloated / Swollen Belly

It is normal that female guppies have a bloated or swollen belly, especially when they are about to give birth. If your female guppy still has swollen belly after dropping the fry, maybe she is constipated or it is possible to have dropsy.

In guppy males, a bloated belly is not normal. They can also become bloated due to constipation if they are overfed. However, if the male guppy presents symptoms such as this on in the picture below, most likely it has dropsy.

Male Guppy Dropsy Disease (source)

Is Guppy Pregnant or Has Dropsy?

In guppies, dropsy is a bit harder to identify, because females develop a huge rounded belly when they are pregnant. Though, after they give birth, their belly will become less bloated.

If the fish spine becomes deformed, the gills become pale or the scales start elevating from the body, your guppy fish has dropsy and you should treat it accordingly.

Is Dropsy Painful for Fish?

For years there is a huge debate around this topic in the science world: do fish actually feel pain. Recent studies shows, that fish actually feel pain. But is dropsy painful? There is no proof about dropsy to be painful for fish, but in humans edema (dropsy) can cause severe pain.

Is Dropsy Contagious to Other Fish?

Dropsy caused by bacterial infection is highly contagious and can pass to other fish too. Though, fish with a stronger immune system can have a natural protection against dropsy.

As mentioned before, you can prevent dropsy if you provide your fish with the right water parameters and a variety of high-quality food.

Is Epson Salt Good for Treating Dropsy?

Some fish keepers report that Epson salt is beneficial in treating dropsy. Some say, that Epson salt will cure dropsy.

It is true, that Epson salt baths will help the fish to recover and can improve the condition of the fish; however, as mentioned before, dropsy caused by a bacterial infection cannot be treated. So, fish keepers who had success with Epson salt, most likely had no fish invested with mycobacteriosis.

Is Dropsy Contagious to Humans?

Humans can also have dropsy disease. In human medicine, this is called Edema. In humans, Edema manifests as the accumulation of fluid under the skin, which can cause sever pain.

Fortunately, fish dropsy cannot be passed to humans. Though, it is recommended to wear rubber gloves, when dealing or treating sick fish.

Should You Euthanize Fish with Dropsy?

If the fish presents an advanced stage of dropsy disease such as protruded scales, you should euthanize it. There are few human ways you can euthanize guppies and other fish:

Anesthetic overdose: this can be done by a vet, because you can’t just buy an anesthetic in a pharmacy. Usually, the fish is placed in a smaller container with half-gallon water. After adding the anesthetic, you should wait at least half an hour, because the overdosed anesthetic will not instantly kill the fish.

Clove oil: is a sedative that can be used to euthanize guppy fish. Mix up 1 gram of clove oil in 10-15 ml warm water. Place the fish in a small container with half gallon water. Add the clove oil mix to the container slowly. The fish need to stay in the solution for at least 15 minutes.

How to Verify Fish Death?

Whatever method is used to euthanize guppy fish, you should ensure that the fish is dead before disposal. A fish can be considered dead 10 minutes after the last gill movement.

The Takeaway

I hope this article has helped you learn about dropsy and how to treat it. Though, if you suspect your fish are sick, you should consult a vet as soon as possible.

If you have any questions, feel free to leave a comment below or send me an email.

Updated: January 8, 2022
Questions & Answers
  1. HI I have a problem with my guppies I’ve had two die already and have noticed their poop was white and they were bloated as well do you know what it is please help thank you.

  2. Monica Spain

    Hi. So glad I came across your article! The picture you have posted above of the male guppy with dropsy is exactly what mine looks like. He’s so swollen that under the chest area it looks like his insides are going to pop out. Almost like a dark area that resembles blood beneath the surface of skin. But I don’t know that that’s what’s there. It’s just what it looks like to my eye.
    However, he swims fine (a tad bit of a wobble but not very noticeable) he is fast, he’s alert, comes to the front of the tank to see me, and LOVES to eat. He goes crazy when food is around. Like he’s been starved. He’s definitely got a great appetite. I’ve had him in a treatment tank 10 gallon for about 3 weeks now. Was treating with Maracyn 2. There’s been no changes in him. No better no worse. Every day I say I’m going to go get clove oil because of how horribly swollen he is and how bad HE MIGHT BE FEELING. But everyday that I think I’m going to use the clove oil, I don’t!! And that’s because he’s still spunky. I would really like to get him out of his lonely treatment tank and either let him go back to the main tank or euthanize him if that’s what’s best. And advice??

    1. avatar

      Hi Monica! Probably he will not get better, at this stage there is not much you can do. I would not put him together with the others, because it can be contagious. It is really hard to tell what is causing it. It can be a bacteria or it is an organ failure. To be on the safe side, keep him separated. I don’t he has any pain, because it is active and eating. A fish that has pain, would hide or would lay on the bottom.

      In my opinion, if the fish is active and you don’t see any sign of pain on him, you should just leave him live. I would only use the clove oil, if his condition would gets worst.

      1. Monica

        Thank you so much for your advice!! One last question then…probably a dumb one lol….but do you think he’s lonely being in a tank with no other fish after he lived with so many others until recently? I feel like he lives such a boring lonely little life now.
        But I’m going to continue on the way I’m doing. Same as your advice. 😁

        1. avatar

          Guppies definitely are social fish, so he might be feeling lonely. If the dropsy is caused by an organ failure (liver or kidney), it is not contagious, so it is safe to keep him with other fish. However, if the dropsy disease is caused by a bacteria, which I described above, that is highly contagious and I don’t recommend keeping him with others. It is hard to tell what causes dropsy, though I think he has a liver or kidney problem.

Leave a Comment

Your email address will not be published. Required fields are marked *