goldfish dropsy

Dropsy in Goldfish

Dropsy - A Deadly Disease in Goldfish

Dangerous and deadly

Dropsy: A deadly disease that can be prevented!

Dropsy is a disease that is almost always fatal in goldfish. This disease is not kind to a little fish and causes suffering and pain. Knowing what to do to prevent it as well as what to look for can save the lives of your goldfish.

If you ever notice your goldfish exhibiting a “pinecone-like” appearance, prompt action is required to save your fish’s life.

Related image

What is Dropsy?

Dropsy develops as a result of kidney failure. The goldfish begins to swell from fluid retention. As the fish swells, the scales are forced outward giving the goldfish a pine cone appearance. Survival at that point is almost always fatal.

This disease is painful and you may find that making the choice to euthanize your fish is the best humane thing to do.

As Dropsy develops in a goldfish, it can infect your other fish. Once one fish comes down with it, you may have to treat the entire tank.

Causes Of Dropsy

  • Kidney dysfunction (renal failure) causing fluid buildup

  • For older fish, prolonged exposure to low temperatures

  • Bacterial in kidney

  • Parasites in kidney


  • Bloating

  • Pinecone appearance from fluid retention pushing scales outward

  • Eyes distended from the socket

  • Body or fins develop redness


  • You will need to purchase medication for treatment at your local pet store.

  • Following dosing directions closely

Process of Elimination: What’s Wrong with My Fish?

If your water quality is good and you can’t figure out why your fish is acting strange or is sick, there are ways to figure out what may be causing it and how to treat it. It is usually a good thing to consult with your local aquarist or pet supply if in doubt.

1.  What are your fish’s symptoms?

  • Appearance (bloating, scales protruding outwards, eyes bulging)

  • Color

  • Behavior (rubbing up against things, laying at the bottom, floating upside down, etc.)

2.  Assess your water quality.

  • Test the water

  • Check filtration system to ensure it’s working correctly (if filtration isn’t working right, oxygen levels can drop)

  • Check water temperature. Drops in temperature can cause fish to get sick.

3. The possible causes 

  • Poor Water Quality is the  #1 cause of sick fish

  • Poor Diet

  • Overcrowding (too many fish)

  • Handling the fish

  • Incorrect water temperature

  • Adding new fish that were not quarantined for two weeks. New fish can be carriers of parasites and other sickness’

Image result for person thinking questioning

Isolating the Diseased Goldfish

Make sure before treating your fish, you assess the water quality and check your filtration system.

A Hospital Tank Should be:

  • A separate tank

  • Used only for quarantining sick fish

Image result for hospital goldfish tank

How do I set up a Hospital Tank

Your sick goldfish will stay in the hospital tank for 3 weeks before transferring it back to the main tank.

  1. Set up a separate tank with a filter system. Include plastic plants, rocks, etc. to provide hiding places for the fish (this helps calms the sick fish.)

  1. DO NOT place any substrate in the hospital tank on the floor of the tank. Loose food gets caught in it causing water quality to decline rapidly.

  1. Transfer some of the established bio media from the filter in the main tank into the hospital tank. By doing this, you introduce the media to the hospital tank that will help to maintain the nitrogen cycle.

  1. Set the filter on the lowest setting. This will ensure that the movement in the water is at a minimum. Rapidly moving water can add stress to the already sick fish.

  1. Using a mesh bag, place some of the main tank’s substrate into a bag and put directly in the hospital tank.

  1. Turn on the heater to reach ideal water temperature of 76 - 80 degrees (F.)

  1. Transfer sick fish over to hospital tank using a net (not your hand.)

  1. Proceed to treat sick fish in the hospital tank.

  1. Add epsom salt to tank to aid the goldfish in removing the water retention and to reduce swelling. Ratio of salt to water is 2 ½ teaspoons of salt to every 10 gallons of water.

  1. Weekly you will:

    1. Change water in the hospital tank

    2. Clean the tank

    3. Repeat salt regime

  1. After the 3 weeks have passed, you can transfer the goldfish back to the main tank.

  1. Continue to monitor all of your fish for any signs of Dropsy. In the event you have other fish exhibit symptoms of Dropsy, repeat the hospital tank steps and treat accordingly.

Keeping a Watchful Eye

Monitoring both your tank water quality as well as your fish’s overall appearance is key to keeping your fish disease-free.

Educating yourself about the signs, symptoms, and causes of diseases that can occur in goldfish provides a valuable resource to refer to.

A watchful eye is the first defense in prevention!