Dropsy Betta Fish Symptoms: Everything You Need To Know

Dropsy – also known as ascites or edema among medical experts – is a common disease used to infect both humans and animals.

Nowadays, dropsy is mostly associated with fish only, as it is caused by an overflow of water of bodily fluids. It can also be used to describe several bacterial infections, which can be a nuisance for aquarists.

So, what are some common dropsy betta fish symptoms? How can you prevent this illness in the first place? And are there any ways to treat your sick fish effectively? Everything lies in today’s article!

Dropsy in Betta Fish: Signs & Symptoms

dropsy betta fish

Now, you must ensure your betta fish are having dropsy. Here are some of the most obvious visual cues to alert you if something goes wrong.

  • Bulging eyes: If you spot bulging eyes on your betta fish, chances are they are experiencing the first stage of dropsy. When the organs shut down and cannot dispel bodily fluid, the excessive moisture starts leaking and pressurizing the eyeball.

Hence, the eyes themselves are pushed slightly outside of the eye sockets.

  • Deformed anus: Having a red or swollen anus is a telltale sign of fish having a bacterial infection.
  • Red skin and fin: Some betta fish are subject to hemorrhage when they fall prey to dropsy. As a result, their skin and fin will turn red.
  • Curved spine: As the excess fluid is not pushed out of the body, it will strain the entire spine.
  • Pale gills: Anemia is a common side effect of dropsy. As betta fish do not have enough healthy red blood cells to sustain their activities, their grills will slowly turn into a pale, silvery shade.
  • Swollen belly: With bodily fluid and water accumulating inside the body, the fish’s abdomen will get much bigger. Sometimes, it even seems like the belly itself will explode.
  • Visible ulcers: Bacterial infection is the primary cause of ulcers. Once you see ulcers forming a straight line along the fish’s body, your betta may have been diagnosed with dropsy.
  • No more feces: Betta fish having dropsy are not likely to consume food. Subsequently, they do not have enough nutrition to create feces. What comes out of the body is mainly mucus and pale feces only.
  • Unusual swimming patterns: If the disease prevents the fish from swimming properly, they will end up letting themselves stay afloat. You will see several bettas near the water surface with little control over how their bodies move.
  • Lack of activeness: When the internal organs do not cooperate and the fish cannot eat, they sure fail to retain a level of enthusiasm. Sick bettas will stop swimming around and playing with one another. Instead, they are likely to hover in one place.

Dropsy in Betta Fish: Causes and Treatment

Generally speaking, dropsy is caused by a bacteria named Aeromanonas. Belonging to a family of bacteria known as Gram-negative, Aeromanonas weakens betta’s immune system and creates multiple opportunities for other harmful factors to kick in.

blue betta

Another reason why your bettas are susceptible to dropsy is their stress level. If your fish do not enjoy their habitat, they stand a higher chance of getting sick. Therefore, do not forget to check the water quality and temperature.

Having to live in unclean water with soaring levels of ammonia and nitrate is a problem. Similarly, bettas do not thrive in cold water. Such combinations are detrimental to their well-being and can quickly shorten their lifespan.

You should also be wary about betta tank mates. Sharing a community tank with aggressive animals means fewer chances to have food. Without proper nutrition, bettas will become lethargic and cannot fight off germs.

Now that you have identified the causes, it is time to examine some possible treatments.

  • Isolate sick bettas: As dropsy is contagious, make sure to remove sick bettas from the healthy ones. You can set up a makeshift tank for these patients.
  • Create the perfect water: A bit of salt is helpful for sick bettas. By replicating betta blood’s salinity, slightly salty water pushes bettas to dispel accumulating water. Here, the ideal ratio should be 1 teaspoon for every gallon.

Then, a partial water change must be performed weekly. Keep in mind that the level of salt must remain relatively stable and the tank is squeaky clean.

  • Feed the fish with antibiotics: There are medicines designed specifically to fight off Gram-negative bacteria. Feel free to mix them with food and water so bettas can consume these meds easily.
  • Provide the fish with a healthy diet: High-quality, fresh food is recommended for sick bettas. You can even grind it if the fish cannot take in solid food yet.
  • Observe sick bettas closely: If things start to improve, you will notice physical signs of the fish getting better. Wait until they go back to their healthy, active stage and transfer them to the community tank.

How To Prevent Dropsy In Betta Fish?

How To Prevent Dropsy In Betta Fish?

Prevention is better than cure. If you want to nip dropsy in the bud, here is what you need to do:

  • Change the water regularly.
  • Keep the ammonia and nitrate level under control.
  • Test the salinity level and see if it is fit for your freshwater bettas.
  • Pick out suitable tank mates.
  • Offer betta fish hiding spots and decor to stay active.
  • Maintain a healthy and balanced diet.
  • Clean the filter every week.
  • Get rid of feces and wastes accumulated at the tank’s bottom.
  • Examine your fish daily to spot timely if something goes wrong.


Determining dropsy betta fish symptoms is just the first step. Once done, you have to take all the necessary measures to get rid of the disease. Make sure to follow the instructions and hopefully, your bettas will come back alive and kicking in no time!