Goldfish Swimming Erratically & Frantically: 7 Easy Solutions

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As a fish owner, I care a lot when my fish present worrying signs. For example, quite a few times, I caught my goldfish swimming erratically across the tank. Luckily, over the years, I learned why this issue occurs and how to deal with it. Now, I am willing to share my thoughts and solutions.

Goldfish typically swim erratically and frantically due to a swim bladder disorder, compromising the fish’s buoyancy. In this case, your fish is also likely to sink to the bottom of the tank. However, goldfish also swim erratically when suffering from a disease, such as Ich, Whirling, and Flukes.

As we proceed, I will share seven recommendations you should implement in your tank to solve that issue and prevent it from reoccurring. That includes measuring your tank’s pH, ammonia, nitrates, and nitrites, using the handy API Aquarium Test Kit (link to Amazon).

Why is my Goldfish Swimming Erratically & Frantically?

Healthy goldfish have equally healthy appetites. They are also active swimmers that spend most of their time exploring the aquarium. However, their swimming shouldn’t be frantic and erratic, and if it is, then you have a problem.

Some goldfish swim erratically because they want to. But such behavior doesn’t last. If your goldfish’s frantic behavior has persisted for hours and even days, you should take the time to find the cause.[1] Some potential sources of frantic swimming in goldfish include:

1. The Goldfish Suffers From a Disease

Because an illness’s presence causes discomfort in fish, it is relatively common for the creatures to respond to that discomfort by swimming erratically. Though, the type of behavior you observe will depend on the illness, for instance:

  • Ich – Most aquarists are well-acquainted with ich. The disease is easy to identify because it causes white spots and specks to appear on the fish’s body. Goldfish with ich won’t stop at merely swimming erratically. They will collide with and rub against the objects in their tank to overcome the discomfort caused by the disease.
  • Whirling Disease – The whirling disease has been imputed to Myxobolus cerebralis, a parasite.[2] While it is most common in Salmonia fish, it can also manifest in goldfish, tetras, discus, and other aquarium fish.[3] The illness causes fish to move convulsively. 

As its name suggests, whirling disease also encourages goldfish to move in a whirling motion.[4] Fish with this illness have additional symptoms such as dark skin near the tail and deformations of the skull.

  • Flukes – If your goldfish is fading in color and its gills produce mucus in excessive quantities, it might have gill flukes, a disease caused by a worm-like parasite that can cause erratic swimming in fish. It would help if you also kept an eye out for anchor worms and fish lice. They can produce similar results.
  • Neurological Damage -Injuries and diseases can cause neurological damage in a fish. As a result, the creature’s motor skills will deteriorate, compromising its ability to swim and leading to erratic movements in the water.
  • Nervous System – Like neurological disorders, nervous system disorders will diminish a goldfish’s ability to swim normally, leading to whirling and circling.
  • Visual Impairment – Some goldfish are continually bumping into objects in the tank, not because they have diseases like ich but because physical injuries and illnesses like cataracts have impaired their vision.

2. Your Goldfish Got a Swim Bladder Disorder

Of all the illnesses that can cause a goldfish to swim frantically, swim bladder disease is the most common. The condition has various causes, including overfeeding, physical injuries, and diseases. The swim bladder controls buoyancy.

Once the organ’s functions are compromised, the goldfish will lose its ability to swim normally. It may sink to the bottom, float to the surface, flip upside down, swim in circles, collide with the decorations, etc.

3. The Water is not Suitable for Goldfish

Goldfish are quite particular about the conditions they expect to find in a tank. You have to keep the temperature, pH, and hardness within the acceptable range. If the water is too hot or cold, the goldfish will express its displeasure by manifesting strange swimming habits.

The same is valid for tanks whose pH is either too high or too low. Aquariums whose parameters are continually undergoing dramatic shifts are just as harmful.[5] Goldfish require stability, and they do not appreciate conditions that are frequently changing.

4. Your Goldfish is Exposed to Toxins

Like swim bladder disease, ammonia poisoning is one of the most common causes of erratic swimming in fish. Goldfish produce ammonia naturally. They expel it from their mouths and gills. The substance also forms whenever waste, leftovers, and dead plants and animals are allowed to decompose in the water.

Even though ammonia is a natural byproduct of a goldfish’s activities, an aquarium is only safe when its ammonia levels are zero. High concentrations of the substance will ruin the gills, causing labored breathing and eventually killing the fish.

You can also expect to see a lot of frantic swimming as a result. But ammonia isn’t your only concern. Aquarists are also expected to test for chlorine, chloramine, lead, copper, and numerous other toxins that may enter your aquarium during a water change or via the new plants and animals you have added to your tank.

5. Inappropriate Water Changes

Water changes are essential to the health of your tank. They keep your goldfish’s environment clean. However, water change can also kill your fish. If your goldfish is unwell, a massive water change will induce stress, and frantic swimming is just one among many symptoms of stress.

Additionally, a water change can cause drastic changes in the chemistry of the water. And as you now know, goldfish hate sudden and dramatic changes. A significant water change can alter the pH and temperature in the tank.

6. You Accidently Introduced Soap to the Tank

Aquarists are expected to clean their tanks occasionally. This includes scrubbing the walls of the tank, removing the algae, and vacuuming the gravel. While this practice is perfectly acceptable, some aquarists do not rinse their aquariums thoroughly. They allow soap to remain on some of the surfaces.

Others forget to rinse their hands properly during a water change. They do not realize that the soapy residue on their hands can contaminate the water. Like most fish, goldfish do not like soap. It is toxic to them, and it can compromise their health, leading to odd behavior such as erratic swimming.

7. The Tank’s Environment is Stressful

If your goldfish is swimming erratically because of stress, but the tank is clean and well-maintained, look at the surroundings. If the room in which the aquarium is positioned has a lot of human traffic, stress is expected.

This also applies to rooms with loud noises such as those produced by television sets, radios, air conditioning units, etc. Some people have observed erratic swimming in fish because of the bright lights in the room.

8. The Goldfish Failed to Acclimatize

Was your goldfish acclimated before you added it to the tank? The shock of moving the creature to an unfamiliar environment in a new tank will induce stress, producing symptoms such as hiding, frantic swimming, lethargy, and loss of appetite.

How to Treat Goldfish That Swim Erratically?

If your goldfish is merely old or it has a genetic disorder, you can’t do much to prevent it from swimming erratically. This is also true for healthy goldfish that are swimming frantically because they want to.

If your goldfish is perfectly happy despite its odd swimming behavior, you can leave it alone. However, if it has additional signs of trouble such as fading colors and a loss of appetite, you can tailor its treatment to match the cause, for instance:

1. Adjust the Water Parameters

Your goldfish cannot recover unless it has the right conditions in the tank. That means maintaining the correct pH, temperature, and hardness; the exact parameters will vary depending on the type of goldfish. 

For instance, fancy goldfish appreciate 68-74 degrees F. I highly suggest that you keep the temperature stable by using a proper heater. Temperature fluctuations tend to stress fish and shorten their lifespan. On that matter, feel free to check my review on the aquarium heater that I use.

Regarding the pH, the desired range for most goldfish is between 7.0 and 8.4.[6] To measure it, I highly recommend the API Aquarium Test Kit (link to Amazon). This bundle will also measure your ammonia, nitrates, and nitrites. All it takes is a few minutes.

You can use household items and commercial products to raise (baking soda, crushed coral, dolomite chipping) or lower (Peat moss, Driftwood, RO Water) the pH.[7] However, as you will see later on, partial water changes are usually the best choice.

2. Replace the Water Properly

This goes without saying. You must change the water regularly. But you need to ensure that the new water parameters are the same as the old water parameters (primarily the temperature). This will prevent the water change from altering the conditions in the tank. 

Don’t forget to apply water conditioners to the new water. Water conditioners will make tap water safe by removing elements like chlorine that can poison the fish. I personally use the API TAP Water Conditioner (link to Amazon).

3. Allow Your Goldfish Proper Acclimatization

Be sure to acclimate new goldfish to new tanks. Most aquarists have had a lot of success with the drip method. They take a goldfish in a bag of its old water, and they float it in the new tank, allowing it to adapt to the temperature. 

Then they slowly add water from the new tank to the bag, allowing the goldfish to grow accustomed to the new tank’s parameters. An adequately acclimated goldfish is less likely to encounter shock when you add it to a new aquarium.

4. Get Rid of Ammonia

You can combat ammonia poisoning by performing a water change. This will lower the ammonia concentration.[8] You should also remove organic contaminants in the tank that have contributed to the ammonia spike, such as rotten leftovers and waste.

Depending on the severity of the fish’s situation, you should consider using a conditioner. It will neutralize the ammonia in minutes, giving you the breathing room you need to clean the tank. For that purpose, I highly suggest checking the API AMMO-LOCK (link to Amazon).

5. Treat Your Goldfish’s Swim Bladder

You can treat swim bladder disease by placing your fish on a 48-hour fast and performing a water change. Once the fast ends, give the fish cooked peas (without the shells) to alleviate constipation. Many aquarists have also encouraged the use of aquarium salt. It combats stress.

If these remedies have failed to produce results, talk to a vet. If an infection caused the swim bladder disease, they would prescribe an effective drug. You can also leave diseases such as ich and the flukes in the hands of a vet.

While some aquarists can get by with essential antibiotics, some illnesses and infections require more potent drugs to overcome. Either way, do not treat your goldfish in the community tank. Make sure to isolate it before it infects other fish in the aquarium.

6. Relieve Stress

Create a stress-free environment for your goldfish. This means adding plants and decorations that can provide hiding places, removing aggressive fish, and using pumps and air stones to prevent oxygen deficiencies from taking root.

7. Feed Your Goldfish Properly

Sick and stressed goldfish require a nutritious diet that includes tiny snails, insects, flakes, and bloodworms, to mention but a few. The omnivores should be fed both animal and plant matter.[9] Without a nutritious diet, the health of a sick and stressed goldfish will deteriorate.

Healthy, well-fed goldfish are less likely to swim erratically. Enriching their diet will also allow them to fight infections efficiently, without letting their current situation deteriorate. If you accidentally skip on their meals, I genuinely recommend considering an automatic feeder. The one I place in my tank is the Eheim Automatic Feeding Unit (link to Amazon).

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If your goldfish is swimming frantically, the best approach is to watch for additional signs. If you see this behavior in other fish as well, test your water. Elevated toxins, including ammonia, nitrates, chlorine, and chloramine, are likely to cause that issue. To get rid of those, replace the water regularly and use a conditioner for tap water.

However, if your goldfish also appears sluggish and possibly sinks to the bottom, its swim bladder may be involved. In this case, your best option is to isolate the fish and consult with a veterinarian.