Minnow with Dropsy

Dropsy In Fish: Causes, Symptoms and Treatment

Dropsy is a condition common among aquarium fish and is typically identified as a symptom rather than the actual disease. A fish showing signs of dropsy may be suffering from underlying problems that need to be separately addressed in order to solve the problem. For fish enthusiasts, here’s what you should know about dropsy.

Signs and Symptoms of Dropsy

The defining symptom of dropsy is bloating. The term itself was originally used to describe swelling caused by an accumulation of fluids, primarily along the tissues and body cavities. The swelling is mainly located in the belly but this is not always the case.Fish Dropsy

In some instances, other symptoms become obvious such as a pinecone appearance where the scales stand out, the anus becomes swollen, the eyes bulge out, the gills are pale, and the feces becomes stringy.

You’ll also notice some behavioral changes such as lethargy of the fish (hiding or staying at the bottom of the tank most of the time), staying near the surface, and apparent lack of appetite.

Note though that these symptoms are progressive. This means that as the condition advances, you’ll be seeing more and more of the above symptoms, starting with the onset of anemia and the loss of colour of the gills. From there, the abdomen starts to swell up and the digestive tract is affected, preventing the fish from properly digesting or excreting.

Early Warning Signs of Dropsy

How To Treat Dropsy
Zebra Danio with Severe Dropsy

Like all health problems, dropsy is best treated before the physical symptoms start to become apparent. During this time, you have no other sign to go on but behavioral changes which can be easily noted if you are observant when it comes to your fish.

Ideally, treatment should be started on the second day you notice some problems with the eating habits of the fish.

Typically, a fish suffering from dropsy will stop eating altogether, often hiding in just one part of the aquarium and steering clear of its peers. This lack of appetite usually extends for two to three days before the belly starts to swell.

Fish Types Affected

Dropsy is not limited to specific breeds of fish. You’ll find that any type kept in the aquarium can develop this particular infection although goldfish seem to be the ones generally affected by the problem. Note though that fish with a low immune system are more likely to suffer from this condition.

If your pet fish are also constantly stressed out, dropsy may become apparent in more than one of them in the tank. As an owner, it is your duty to observe the inhabitants of the aquarium and make sure that there are no environmental factors that could trigger the problem.

What Causes Dropsy In Fish?

There are several possible causes of dropsy but the underlying problem stems from negative bacteria that leads to the infection. The infection takes hold of the fish with a weak immune system, the weakened state often caused by the following problems:


The fish tank should be kept at 78 to 80 degrees Fahrenheit – the perfect temperature to promote digestion in aquarium fish.

Note though that the number is variable, depending on the kind of breed you have. Ideally, you should research the exact temperature preferences for your fish and set your aquarium to that setting. This way, you’d be 100% sure that the environment is to your pet’s liking.

Bad Water Quality

Poor water quality means bacteria floating in the water, thereby compromising the immune system and increasing the chances of dropsy. Fortunately, you can easily maintain water quality through proper hygiene.

This includes cleaning the water filter on a routine basis, using the proper aquarium cleaning agents and generally making sure that your aquarium maintains a balanced environment for the proper health of the fish. An important step in taking care of your fish’s water is by using a water conditioner in any water that you put into the tank. We always recommend the API Stress Coat water conditioner or the Seachem Prime Conditioner which works in both fresh and saltwater.

Proper Nutrition

Of course, don’t forget the possibility of improper nutrition which usually stems from feeding your fish poor quality food. Make sure you’re giving them approved brands with some fresh servings thrown in for better health.

Depending on the species of fish in your tank, a good tropical fish flake food should be a staple of their diet. The one that we use and recommend is TetraMin Tropical Flakes.

A good fresh food feed would be a shelled pea, provided at least twice in the day.

A shelled pea is of the right consistency and nutrition to keep your fish healthy, especially when suffering from dropsy. Note that the routine of your feeding also comes into play. Ideally, fish should be sped sparingly and no more than twice a day.

Other contributing factors to dropsy include bullying of other fishes, thereby causing stress and any physical injury the fish might have. A newly transferred fish might also show symptoms due to the stress of being moved to a different tank.

How To Treat Dropsy In Fish

How To Treat Dropsy

Dropsy is not something you can cure instantly, bearing in mind that there are several possible reasons for it. However, fish enthusiasts can try to address the problem and eventually cure the condition.

It is not unheard of for a fish to recover from dropsy, but it does require care and attention on the part of the owner. That being said, the following are the steps to care for a dropsy-infected fish.

Antibacterial Medications

The quickest and easiest way to treat dropsy in fish is to add an antibacterial remedy to your aquarium. The one that has consistently served us well is API Melafix. It’s one of our secrets that we love to share with new fish keepers. Keep a bottle in your cupboard because you never know when you’re going to need it.

Chewy.com has an autosave feature that allows you to subscribe and save money on each delivery. It’s worth checking out so that you’ve always got some Melafix on hand. It really is the best cure-all treatment. (P.S You can currently get 30% off your first Autosave order)

The majority of common diseases can be cured with a good diet, an antibacterial remedy and proper water conditions. Hopefully, this guide has given you the knowledge and inspiration necessary to cure dropsy in fish, as well as prevent it from occurring again in the future.

Quarantine Your Fish

The first step in treating dropsy is through quarantine. Although the condition is not always contagious, quarantine of the infected fish is an excellent precaution to make sure that none of the others will be infected.

Salt Treatment

Once you’ve isolated the affected fish, it’s time to add some salt into the aquarium of the infected fish. The rule of thumb is that you have to add 1 teaspoon of salt for every gallon of water. Change the water on a routine basis, still adhering to the 1 teaspoon for every 1 gallon added to the container.

The best salt for home aquariums is API Aquarium Salt (the one we order is pretty cheap from Amazon). It’s always helpful to have some on hand for when you’re dealing with sick fish (which unfortunately is a lot more often than you think).

Feed Your Fish a Healthy Diet

A good diet (along with perfect water conditions) is the best way to prevent and treat common diseases. The food you feed your fish will depend on the individual species, but as a rule of thumb, the bulk of the diet should be made up of a quality pellet or flake food like the TetraMin Flakes, with additional supplementation of live foods, frozen foods, vegetables and/or freeze dried foods like the Tetra BloodWorms.

Similar Posts


  1. logan Logan Price says:

    Yes, Pauline. The treatments listed here will work with pond fish :)

  2. Fiona Wang says:

    Hello! So I’m super late but hope someone can help: do I use salt and melafix together? I just noticed my betta fish (2.5 gallon, by himself) is bloated and pineconing so I added the salt, 2.5 tsp. Can I add the Melafix with the salt? The label says nothing about any interactions with the salt.

    1. Anonymous says:

      Hey, you should not use melafix or bettafix with bettas. It contains tea tree oil which can be very harmful to their labyrinth organ

  3. Hi Guys!

    My oranda goldfish has dropsy and I think I catched in early stage because he still eating, still active, no bulge eyes but I noticed pineconing. I put him in a hospital tank and treating him with Melafix and Epsom salt. I did A LOT of research and I noticed in this case more people recommend Epsom salt instead of Aquarium salt. What is your opinion guys? Which one is more effective?


  4. I’ve done this treatment with fish before, and it doesn’t work. Granted, my guy was progressed pretty far by the time I realized what it was. (That was my first time ever dealing with it) By the time you have pineconing, they’ve had it for awhile. If you’re gonna use Melafix, it has to be used extremely early, otherwise it’s not aggressive enough.
    Dropsy is caused by a gram negative bacterial infection, which means the cell wall of this bacteria type is thin. You have to purchase with that in mind.
    There are many fish antibiotics that are the same price as Melafix and can actually save your fish. The biggest downfall to these medications is they can be harmful to invertebrates, so dose at half the strength if you’re dosing your whole tank with those guys in it.** Otherwise, setting up a hospital tank and separating the sick fish will be your best bet.
    I have a Betta and an Ember tetra that have it right now, so I’ll be dosing their original tank at half strength for 2 days with a 20% water change in between to dilute and give the inverts a tiny break. Meanwhile, betta and tetra will be in their hospital tank getting full strength for 10 days.
    I bought two different medications to try. I’ll be using KanaPlex by Seachem first, which uses the medication Kanamycin which attacks both gram negative and positive bacteria, but is more notorious for negative.
    And the second is called Amoxicillin by Fish Aid. This one also attacks both gram negative and positive, but it works better on gram positive. It works on some gram negative and I’ve read research that says it does work on Dropsy specifically, but there’s not enough evidence for me to rely on this solely, so hence buying the Kanamycin.
    **Also note, some of the beneficial bacteria in your tank are gram negative as well, so this is another reason to set up a hospital tank. Dosing your whole tank at full strength for a full period of time can stress out your healthy fish and cause their immune system to weaken as well.
    Taking time to learn the chemistry of fish tanks can really really help with the health and longevity of your fish’s life. I’ve had sensitive fish live for years longer then what the life expectancy says online. It’s worth having the deeper knowledge instead of relying on what other people have experimented with because at the end of the day, it’s a life your saving, not just some mindless thing in the water.
    I wish you all the luck in the world!

    1. Hey everyone! I have a black moor goldfish who has dropsy. He is pineconed and not eating. He is also belly up and breathing rather slow. He definitely looks like he is suffering. I’ve tried everything I can think of for him. I’ve used both kanaplex and maracynoxy for antibiotics and added aquarium salt to his tank. He is quarantined in a 10 gallon tank. I gave him an epsom salt bath last night for 15 minutes. Nothing is working and I feel so bad for him. Please help! Thanks!

  5. Hi I have 6 goldfish , 4 from about 8 years ago and 2 of their babies who are about 3 now. One of them looks like he is literally on the edge of exploding and he does have bulgy eyes but not really any pinecone scales, a little on the bottom but not anywhere else. Im guessing it’s not contagious since none of my other fish are that fat but I was jus wondering what we need to do in order to get my fish back to normal. He’s been looking like this for a few months now but we don’t know what it is, we don’t know if its dropsy or not.

  6. Anonymous says:

    Is the Aquarium salt safe to put in the tank with Guppies, Mollies, and Tetras?

    1. Bacon Lady says:

      Yes. I have a breeder tank with guppies, a couple snails, and a couple of fancy shrimp. I don’t go as high as 1 tsp per gallon, though. I put in 1 Tbs when I do a 25% water change, so that’s 3 tsp per 10 gallons. But only with changes. Water evaporates, salt doesn’t. So if you’re only adding water to a tank that’s gotten low, then don’t add salt.

  7. Rebecca Rogers says:

    I have a fish that exhibited pine cone scales on his tail. He was acting normal and eating. I treated him with antibiotics for five days and added a salt treatment to the water as well. The pine cone has disappeared and he seems healthy still. I’m not sure what was wrong with him but it’s been over a week now and I am wondering if I should add him back to my aquarium.

  8. MPAquariums says:

    hi, i have 6 guppies 2 male 2 females 2 babies, one of the females have pine coning but nothing else. what should i do, with guppies do i use Epsom salt or melafix. I just really hope that they will be ok. plz help me.

    1. Hello! When female guppies form a pinecone, depending on the severity, it could be pregnancy or dropsy. How severe is the pine coning?

  9. My goldfish has dropsy started treatment yesterday. Do I add salt every fay and do I give the antibiotics everyday, if yes how often do I add the salt and is there any guarantee in recovery ? Pls answer my questions as I’m very worried

    1. Hi Sam! Can you give us an update on your goldfish?

Leave a Reply

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