Why Is Goldfish Staying In The Corner Of The Tank? Causes & Solutions

Watching little and beautiful goldfish swimming around the tank is a common hobby of fish keepers. But what if your pet doesn’t like to move?

Why is your goldfish staying in the corner of the tank? There are several reasons for this problem, each with a particular solution.

Let’s follow these helpful guides!

Why Is My Goldfish Staying In The Corner Of The Tank?

Once your pets can’t find a pleasant place to swim in the tank, they will move to the corners. Please scroll down for a detailed explanation.

The tank is too crowded.

The goldfish may feel that they don’t have enough personal space.

You should either buy a larger aquarium or move the violent fish to another container if the tank is too crowded or has aggressive species.

Keep in mind that one goldfish needs about 30 gallons. Then, for every new fish, you’ll need an additional 10 gallons.

If you can’t remove aggressive out of the tank, add decorations and plants to block their sights. If none of these works, insert a divider as a last resort.

The tank is overcrowded 

Your fish likes to stay in the corner.

Your pets may sometimes prefer one area of the aquarium over others.

Perhaps they feel more protected or notice more algae blooms adjacent. They may choose to stay there since you frequently give them food from that spot.

Since it’s a preference, you don’t need to worry about your pets staying in the corner. To ensure it’s not an indication of something terrible, you should observe them.

If you want the fish to swim around, add some new plants and decorations. Introducing tank mates can also be a good idea.

They look for the best temperature zone.

The ideal water temperature will vary depending on the type of goldfish. Generally, this species likes a temperature range of 68 to 74°F.

The heat may not be the same on every side of the aquarium. Some spots can be too cold or too hot for your pets. Hence, they move to the best temperature corner for their bodies.

If you notice your goldfish staying in one spot, try shifting the aquarium’s thermometer to different positions. Then, check if the temperature has changed after a few minutes. You can add another heater to disperse the heat evenly.

They can’t withstand the strong water flow.

A filter is vital to maintain the goldfish aquarium clean. Yet, sometimes the rate at which the water leaves the filter may be overwhelming.

Your pet will most likely stay in the less-current-strong zones, and they find the corners ideal.

You can solve this problem by angling the filter into the aquarium’s side to minimize the circulation through the center. To slow the water flow, you can insert a filter pad into the filter tip.

Also, check the filter carefully. The problem may arise from the speed mode you have set and forgot to adjust.

They are sick

When your pets feel ill, they want to hide for safety. It is best to examine the fish for any disease-related signs. Some typical symptoms of the disease include clamped fins, lethargy, and a poor appetite.

Other specific symptoms will also vary by condition. You’ll see white spots on their body if they have it, and they will look bloated if they have constipation.

Wherever possible, you must diagnose the disease and start treating it immediately. Your little pets can’t suffer for longer.

You can prevent the risks of diseases by keeping the aquarium clean, doing regular water changes, isolating new or sick fish, and providing your pets with high-quality food.

Check for signs of disease

They are suffering from ammonia poisoning.

Ammonia poisoning happens when the aquarium’s levels of ammonia, nitrates, and nitrites are too high. This process happens quickly and can kill your pets in a few hours.

It may be ammonia poisoning if the fish is gasping for breath at the corner of the tank. Moreover, you might also notice that their grills are turning red.

If you are sure that your goldfish have ammonia poisoning, the solutions will be as follows:

  • Test the water using the API test kit. If the ammonia nitrate or nitrite is too high, perform a half water change straight away.
  • Cycle the aquarium before introducing new fish. You need to leave the container empty for several weeks to allow the beneficial bacteria to consume ammonia.
  • Do not overstock the aquarium.
  • Remove the tank waste regularly.

Avoid ammonia poisoning at all costs

Extra Tips To Keep Your Goldfish Active

Each cause for your goldfish staying in the bottom corner of the tank comes with a specific solution. Yet, there are some common remedies for this problem.

Give them more hiding places.

If there aren’t enough places for your fish to hide, they’ll go to a corner.

The goldfish aquarium needs more plants and caverns as your fish will feel secure hiding among these objects.

Buy a high-quality heater.

Investing in a reliable heater is an easy method to deal with the issue of fluctuating temperature.

Make sure the heater effectively warms the entire tank without overheating your pets. You could want more than one heater if your aquarium is too large.


Your goldfish may stay at the bottom of the tank for multiple reasons. They may feel sick or try to protect themselves from the overcrowded habitat.

It would be best to observe your fish’s behavior and bodies for signs of sickness and ammonia poisoning. Then, you can figure out a way to tackle your problem.

Hopefully, you will find this article helpful. Thank you for reading!