Why Does My Goldfish Have White Spots?

Written By Daniel Abi  |  Disease  |  0 Comments

Goldfish are beautiful, hardy creatures that are pretty straightforward to care for. But picture this. To your horror, one day, you notice your fishy friend sporting a rash of tiny white spots across his body and fins!

Help! Why does my goldfish have white spots?

Well, the problem could be quite innocent if you have a male goldfish in breeding condition, or it could be more serious if your pet has White Spot disease or Ich.

Read this guide to learn why your goldfish could have white spots, how to treat your pet and prevent the condition from happening again.

What are the white spots on goldfish?

There are two primary causes of white spots on goldfish; breeding tubercles and a parasitic infection called Ich, Ick, or White Spot disease.

Breeding tubercles

Breeding tubercles are tiny white keratin-based nodules that mature male goldfish develop during the breeding season when the water warms up and the days are longer.

The nodules usually develop on the leading rays of the fish’s pectoral fins and gill covers, but you can also sometimes see them on the creature’s head and around the eyes. 

Occasionally, you can see breeding tubercles on the fish’s body, although that is quite unusual. Note that when breeding tubercles develop on the body, they typically follow a neat pattern that matches the contour of the scales. In the case of Ich, the spots are scattered randomly and are usually considerably smaller.

The hormone testosterone causes the development of breeding tubercles, and their numbers vary from a few on the pectoral fins to dozens all over the goldfish.

Interestingly, male fish with the most tubercles are thought to be regarded by females as a good catch, being healthier and more likely to reproduce successfully than less dominant males. That means the female fish will pick a male with plenty of tubercles since a successful spawn and robust fry are likelier.

The tubercles are shed once the breeding season ends, and the fish’s appearance quickly returns to normal.

What is Ich?

Ich, Ick, or White Spot disease, as it’s sometimes called, is a condition caused by an external aquatic protozoan parasite called Ichthyophthirius multifiliis. The condition is often called White Spot disease after the rash of white spots that appear across the fish’s body and fins.

The Ich parasites generally attack fish with lowered immune systems. So, if your goldfish are recovering from a disease, sudden temperature changes, or a move from the fish store to a home tank, they could be vulnerable to White Spot disease.

In fact, the parasites are commonly found in the water of a healthy aquarium, waiting for their chance to attack your goldfish!

Ich symptoms

Ich presents with various symptoms, including the following:

Laboured breathing: Oxygen deprivation causes the fish to breathe more heavily as it attempts to pull more oxygen into its body.

Flashing and rubbing against objects: The Ich parasite causes intense irritation, so the fish flash and rub against solid objects and plants in the aquarium in an attempt to relieve the itching.

White spots appear on the fish: You won’t be able to see the Ich parasites at first. However, once they start feeding on the fish, they encyst and appear as tiny white dots across the body, gill covers, and fins.

White patches appear on fins and scales: As the disease progresses and the parasites spread, white patches sometimes appear on the goldfish’s scales, fins and gills.

The Ich life cycle

You must know more about the parasite’s life cycle to understand how to treat and prevent Ich.

Feeding stage

Every one of those little white spots on your goldfish is actually a nodule formed by an Ich parasite on the fish’s skin. This is typically called the feeding stage. Ichthyophthirius multifiliis, now called a trophozoite, fixes itself to the fish’s skin and eats its body fluids until the parasite is ready to reproduce.

In fact, the parasites feed off the goldfish for a few days before they become visible as wide spots. 

Note that Ich trophozoites are resistant to most medications during the feeding stage. For that reason, it’s better to wait until they emerge from the protective nodules when they become more vulnerable.

Encapsulated dividing stage

When the parasites have finished feeding off the fish, they detach themselves from the skin and move to a plant, decoration, or piece of substrate, where they develop into cysts. 

Now, the parasites are called tomonts, and the encapsulated dividing stage starts. In just 24 hours, hundreds of new parasites called theronts are produced by each cyst!

Free-swimming stage

Once the cysts release their cargo of theronts, the free-swimming stage begins. Now, hundreds of new Ich protozoa start swimming around your aquarium, looking for hosts to grab onto and start feeding off.

At this stage, you should begin treating the Ich disease since the parasites are most vulnerable when not surrounded by a protective cyst. So, you must kill off as many free-swimming parasites as possible before they attach to your goldfish.

Once the parasite fixes itself to a host, the cycle begins all over again.

How to treat Ich

Remember that not all the Ich parasites in your goldfish tank will be at the same life stage. For that reason, you must continue treating the tank for the whole course. If you don’t, you might miss a few parasites during the encapsulating dividing stage, and the infection could start all over again.

Natural Ich remedy

This natural Ich treatment uses just heat and aquarium salt to cure White Spot disease, making it a great option for you if you don’t want to use chemical treatments in your tank.

  • Start by increasing the water temperature in your fish tank by a few degrees and keep the water at that temperature for up to ten days. The heat prevents Ich from dividing into hundreds more parasites once it detaches from your goldfish.
  • Next, add aquarium salt to the water to encourage your goldfish’s slime coat to develop, protecting them against Ich reinfestation. Carefully follow the dosage instructions on the salt packaging, and don’t overdose the tank.
  • Finally, the heat and salt will attack free-swimming Ich protozoa and kill them.

Note: If you have scaleless fish in your collection, know they cannot tolerate large salt doses. So, treating your goldfish in a hospital tank is best to keep the others safe.

Commercial Ich medications

There are many effective, safe Ich medications on the market, all of which are available in your local fish or pet store.

If you keep invertebrates in your tank, double-check the medication to ensure it doesn’t contain copper, which is fatal to snails and some other inverts. 

Follow the instructions carefully on the packaging, and be sure to complete the recommended course of treatment. You can also hasten the effectiveness of the treatment by raising the water temperature by a few degrees during the treatment.

Can goldfish recover from Ich?

Yes, provided that Ich is caught early and treated appropriately, your goldfish should make a full recovery from it.

Can goldfish survive Ich without treatment?

If you don’t treat Ich or delay treatment for a long period, Ich could kill your goldfish.

Remember that Ich typically attacks fish that are already weakened by disease, stress, or injury. So, the fish is probably not strong enough to fight off the parasites without some help from you. 

In severe cases, the parasites infest the goldfish’s gills, preventing the fish from breathing efficiently, and oxygen deprivation or suffocation can result.

Will Ich go away by itself?

Sometimes, if a goldfish is eating well and remains active, stress-caused Ich can resolve itself after several weeks or months.

However, there is usually some underlying issue that leaves the fish vulnerable to the parasite, and, as a responsible owner, you should investigate the problem and treat your pet accordingly.

How to prevent Ich

In the case of Ich, prevention is easily achievable and is much better than cure!

Here are a few tips on preventing White Spot disease from affecting your precious goldfish.

  • When buying goldfish, check them over thoroughly before leaving the store. Don’t buy a fish showing signs of sickness, inactivity, or that’s not swimming socially with its tank mates. Never buy a goldfish that’s flicking against objects in the tank or displaying white spots on its body or fins.
  • Place new fish in a quarantine tank for at least two weeks before introducing the newbies to your main display tank. If your fish begins showing symptoms of Ich during that time, you can start treatment.
  • When I buy new fish of any species, I like to treat them with broad-spectrum antibacterial medication during the quarantine period. Even if the fish appear to be healthy, I reckon it’s better to be safe than sorry.
  • Acclimate new goldfish with water from your existing aquarium rather than pouring pet store water into the tank. Diseases or parasites could be swimming around in the water, so always play it safe.
  • Live plants can also harbour parasites, including Ich. I recommend placing new plants in quarantine for at least two weeks if you buy them from a tank where fish are kept. You can buy live young plants packed in sealed plastic containers from good pet stores. These plants are grown in a sterile, disease-free environment, so these are the safest bet for your tank, and you don’t need to quarantine them before planting.
  • If you’ve used a fish net to remove new fish from a travel bag, don’t use the same net again until it’s completely dried out. For all you know, parasites could have hitchhiked on the net, and you might accidentally infect your main display tank if you’re not careful. Keep a spare net, and always use a clean one to transfer fish to quarantine.

As you can see, keeping Ich out of your goldfish tank is straightforward and easy with a little bit of effort and forethought.

Final thoughts

If your goldfish develops white spots, there are two probable causes. If the fish is a healthy adult in breeding condition, there’s a good chance the white spots are breeding tubercles, which will disappear once spawning has finished.

The other probable cause of white spots on your goldfish is the Ichthyophthirius multifiliis parasite. Fish with Ich infestation flick or rub against objects in their aquarium, and tiny white dots develop across the gills, body, and fins.

Ich is treatable by raising the water temperature by a few degrees for ten days and treating the tank with aquarium salt. Alternatively, you can use an over-the-counter White Spot treatment to do the job.

Fish with Ich usually recover once treated, although severe cases that are not dealt with can be fatal.