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The Goldfish Gazette, Issue #090 Disease Outbreak First Steps
June 29, 2021

Goldfish Care Tips

A Free Monthly Resource For Goldfish Enthusiasts
June 2021
Issue #090

In This Issue
Disease Outbreak First Steps

A disease outbreak can occur at any time, and is often noticed when you are about to leave for work.
Having a few essential medications and equipment on hand can save you stress and your precious pets.

Disease Outbreak First Steps

Clamped fins indicate sickness in Goldfish

When a disease outbreak is first noticed, the most important first steps are to remove anything obvious that caused the outbreak, (i.e. toxic water), and start initial treatment for the most likely disease(s).

Disease Outbreak Signs

Some outbreaks are obvious such as in extreme cases fish dying or your fish covered in white spots.

More subtle signs are if your fish are bottom sitting, or at the surface with fins clamped close to the body.

No healthy Goldfish will have clamped fins…ever.

Time is of the Essence

Because poor water quality does cause many Goldfish diseases, that is the first thing to check with your water test kit. You may have had a filter failure, or a fish has died out of sight causing an ammonia spike.

Very small amounts of ammonia will kill fish, so determining water is the source of the problem quickly means you know you need to make a large water change immediately, and not leave it until you come home from work.

Fresh, clean water is the cheapest, easiest initial treatment for any Goldfish illness and provides valuable time to assess what the problem is.

Essential items – Water test kit, water conditioner

Many diseases are fast acting. Parasites such as Costia can kill a Goldfish within days, and the symptoms may have gone unnoticed for one of those days.

Unfortunately, the symptoms for many diseases are the same, clamped fins, labored breathing, red patches on the body.

If it is only one fish displaying symptoms (so far), isolate it in your hospital tank and add a teaspoon of aquarium salt per gallon.

Essential items – hospital tank, aerator, sponge filter, aquarium salt.

You will increase the salt by another teaspoon per gallon when you arrive home, and a further teaspoon the next morning.

Disease Diagnosis

Apart from diseases like white spot, diagnosing what illness a Goldfish has without a microscope is nearly impossible, but you can narrow down treatment options.

If you haven’t introduced any new fish or plants into your aquarium recently, you can eliminate anchor worm and lice. These freshwater parasitical crustaceans are more of a nuisance than a danger, and as long as new fish are quarantined and plants sterilized, you will remove the problem at source.

A fungal attack is obvious, and usually affects only one or two fish. If you have treated new fish in quarantine for parasites, the fungus will probably be caused by injury or poor water conditions. The fresh water and salt will start the healing process, but an anti-fungal medication such as Methylene Blue should also be added to the hospital tank.

Essential Item – Methylene Blue

If you haven’t treated for parasites such as flukes or Costia during quarantining, then they have to be included as a possible primary disease cause.

The salt treatment will deal with protozoan parasites such as Costia but not flukes.

You will need to administer a Praziquantel medication such as API General Cure or Hakari PraziPro.

Essential Item – Praziquantel based medication.

The next most probable disease outbreak will be bacterial.

As bacteria and fungal spores are always present in aged water, a bacterial outbreak will usually be caused by poor water conditions weakening a fish’s immune system.

Clean water and salt are all that are necessary, as long as you are certain you have eliminated flukes from your Goldfish population. If not, you will also need to treat with a Praziquantel based medication.


You don’t need a lot of medications or equipment to deal with a disease outbreak.

Any plastic container can be a hospital tank, and salt, Methylene Blue and a Praziquantel based medication will cure most diseases.

Comments? Ideas? Feedback? I'd love to hear from you. Just reply to this e-zine and tell me what you think, or what topics you want covered.

Next Month's Topic

Mixed Varieties Feeding

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