Cory Catfish Glass Surfing: (Reasons & 5 Rapid Solutions)

If you’re a proud owner of Cory catfish, you might have noticed a peculiar behavior known as “glass surfing.” While it can be a bit concerning, this Cory catfish glass surfing behavior is quite common among Cory catfish and can usually be addressed with proper care and attention. 

This comprehensive guide will explore why Cory catfish engage in glass surfing and provide five rapid solutions to address this behavior.

Whether you’re a seasoned aquarist or a beginner, understanding and tackling glass surfing is crucial for the well-being of your beloved aquatic pets.

Why Is My Cory Catfish Glass Surfing?

Corydoras glass surfing is an expected behavior observed in Cory catfish and other species. This behavior occurs when the freshwater fish repeatedly swim along the sides of the aquarium, seemingly “surfing” along the Glass.

There are several reasons why a Cory catfish may exhibit glass surfing. One possibility is that the aquarium may be too small or have poor tank conditions.

Insufficient space or inadequate water parameters can be stressful for fish, leading them to display odd behaviors like glass surfing.

Corydoras glass surfing

Another reason could be the tank’s lack of hiding spots or decorations. These fish naturally seek out hiding places to feel secure, and a lack of these may induce erratic swimming patterns.

Addressing these issues and providing a proper environment for your Corys catfish is essential to ensure their well-being and minimize stress.

5 Main Reasons Why Cory catfish glass surfing

Glass surfing, the behavior where Cory catfish swim around in the tank, might initially seem strange. However, there are several valid reasons behind this activity:

– Water Parameter Issues

Cory catfish are highly sensitive to water conditions. Even minor ammonia, nitrate, nitrite, and water temperature fluctuations can trigger glass surfing. Maintaining stable and suitable water parameters is crucial to keep your cory catfish content.

– Poor Water Quality

If your aquarium water quality is compromised, your cory catfish might engage in glass surfing. High levels of pollutants can stress them and lead to erratic swimming behavior. Regular tank water testing and maintenance are essential to prevent this.

– Incompatible Tank Mates

Aggressive or overly active tank mates can cause your fish to feel stress, leading to glass surfing. Ensure that your tank mates are peaceful and compatible with the nature of Corydoras glass surfing.

– Hiding Places and Hiding Spots

Cory catfish feel more secure when they have hiding spaces at the bottom of the tank. A lack of hiding spots or the presence of aggressive fish in the tank might drive them to swim near the glass walls.

– Insufficient Hiding Places

Cory catfish thrive when they have ample hiding places at the bottom of the tank. They might resort to glass surfing to escape potential threats if these spots are limited.

5 Rapid Solutions to Address Glass Surfing

Now that we’ve explored the reasons behind glass surfing, let’s dive into five rapid solutions to tackle this behavior and ensure the well-being of your cory catfish.

1. Check Water Parameters Properly

Regularly test your water for ammonia, nitrate, nitrite levels, and temperature. Keeping these parameters within the optimal range will significantly reduce glass surfing behavior.

2. Create Ideal Hiding Places

Provide a variety of hiding places at the bottom of the tank. Consider adding aquatic plants, decorations, and rocks to mimic their natural habitat and give them a sense of security.

3. Choose Suitable Tank Mates

Opt for peaceful and compatible tank mates. Avoid aggressive fish that could stress out your cory catfish. A harmonious community tank environment is essential.

4. Maintain Proper Tank Conditions

Ensure your aquarium is well-maintained. Perform regular water changes, clean the substrate, and monitor water flow to prevent poor water quality, which can lead to Cory cat glass surfing.

5. Introduce Cory Catfish Carefully

When introducing new fish to the tank, do so gradually and carefully. Sudden changes in the tank environment or the addition of aggressive fish can trigger glass surfing in cory catfish.

Why Is My Cory Catfish Swimming Crazy?

If your Cory catfish is swimming wildly, there could be a few reasons behind this behavior. Cory cats are known for their active and playful nature, so it is not uncommon to see them swimming frantically.

However, if the swimming behavior seems abnormal or uncontrolled, it could signify distress. One possible reason could be poor water quality in the tank.

Cory catfish are sensitive to water conditions, and if the tank water is polluted or lacks the proper parameters, it can cause them to exhibit odd swimming patterns.

Another reason could be catfish glass surfing, where the fish constantly swims against the Glass. This behavior is usually a result of stress or boredom and might be alleviated by providing a more suitable environment with plenty of hiding spots and stimulation.

Why Are My Cory Catfish Swimming Up and Down?

Cory catfish swim up and down for several reasons. One possible explanation is that they are trying to establish their territory. By swimming up and down, they show dominance and defend their space from other fish.

Another reason could be that they are searching for food. Cory catfish are bottom-dwellers, and swimming up and down allows them to explore different areas of the tank in search of tiny particles of food that may have settled there.

Additionally, Cory catfish may swim up and down as exercise. They are energetic and active fish, and swimming up and down helps them stay healthy and maintain their muscles. Overall, the behavior of cory catfish swimming up and down is natural and beneficial for their well-being.

What to Do When You Find Corydoras Cats Swimming All Over the Tank?

Finding your Cory cats swimming all over the tank could signal that something is off. Cory cats are bottom-dwelling fish and usually prefer to stay close to the substrate.

Cory cat breeding

When they start swimming all over the tank or spending timet glass surfing, it could indicate stress or discomfort. You should check the tank parameters such as water temperature, pH, ammonia, and nitrate levels to ensure they are within the appropriate range.

Ensure the tank is adequately oxygenated and has enough hiding spots for the Cory cats to feel secure. Introducing tankmates compatible with Cory’s cats can also help reduce stress.

If the behavior persists, it is advisable to consult a veterinarian or a knowledgeable fish keeper for further guidance.

Why Do Corydoras Swim to the Surface?

Corydoras, also known as Cory catfish, are bottom-dwelling fish that swim close to the substrate. However, you may occasionally notice your Cory darting or darting to the surface. This behavior is usually observed when there is a lack of oxygen in the water.

As these fish depend on oxygen through their gills, poor water conditions or low oxygen levels can prompt them to swim erratically toward the surface in search of oxygen-rich water.

Ensuring proper aeration and water quality is crucial to avoid such behavior. Regular water changes, maintaining a clean tank, and providing adequate filtration can help create a healthier and more oxygenated environment for Corydoras and other fish species in the aquarium.

Commonly Asked Questions about Corydoras Cory Cat Swim (FAQs)

Why does Cory catfish glass surf?

Cory catfish glass surf due to poor water quality, incompatible tank mates, and insufficient hiding places. It’s often a sign of stress or discomfort.

How can I stop my Cory catfish from glass surfing?

Stop Corydoras glass surfing by maintaining stable water parameters, providing hiding places, choosing suitable tank mates, and ensuring proper fish tank conditions.

Is Glass surfing harmful to Cory catfish?

Glass surfing isn’t harmful but a sign that something might be wrong in the tank environment. Addressing the underlying issues is essential for your fish’s well-being.

Can water temperature affect Glass surfing?

Yes, water temperature fluctuations can trigger Corydoras glass surfing. Ensure you maintain a consistent and suitable water temperature for your Cory catfish.

How do hiding places help reduce glass surfing?

Hiding places gives Cory catfish a sense of security and reduces stress. They are less likely to engage in glass surfing when they have ample hiding spots at the bottom of the tank.

Can aggressive tank mates cause glass surfing?

Yes, aggressive or overly active tank mates can stress out Cory catfish, leading to glass surfing. Choose peaceful and compatible tank mates to prevent this behavior.

What is Cory Catfish Glass Surfing?

Cory Catfish Glass Surfing refers to the behavior of Cory catfish darting to the tank’s surface and rubbing against the Glass.

Is Glass Surfing normal when Cory catfish are first introduced to a tank?

Yes, it is typical for Cory catfish to display glass surfing behavior when they are first introduced to a tank. They might be exploring their new environment and trying to familiarize themselves with their surroundings.

Are there any specific tank mates that may cause Cory catfish to glass surf?

Incompatible tank mates can sometimes cause stress in Cory catfish, leading to glass surfing. It is essential to research and choose tank mates that are compatible with Corydora catfish.

How can I keep my Cory catfish happy and prevent glass surfing?

To keep Cory catfish happy, ensure the fish have enough hiding spots, check the water parameters regularly, and provide a suitable diet. Maintaining a well-established aquarium with compatible tank mates can also help reduce Corydoras glass surfing behavior.

Is glass surfing always a cause for concern?

Not necessarily. While glass surfing can indicate stress or discomfort, it is not always something to worry about. However, monitoring the behavior and ensuring it doesn’t persist or worsen is essential.

What are some reasons why my Cory catfish might be glass surfing?

Some possible reasons for Cory catfish glass surfing include water parameter issues, territorial disputes, lack of hiding spots, insufficient tank size, or aggressive tank mates.

Are there different types of Cory catfish that are more prone to Glass surfing?

While different species of Cory catfish may exhibit glass surfing behavior to varying degrees, it is not necessarily linked to specific types of Cory catfish. Various factors can influence the behavior, including the tank environment and the individual fish’s personality.

Will Cory catfish stop glass surfing if they have enough food?

Providing a sufficient and balanced diet for Cory catfish is essential but may only resolve glass surfing behavior partially. While hunger can contribute to stress and glass surfing, addressing other factors, such as tank mates and overall conditions, is essential.

Is Glass surfing a popular activity among Cory catfish?

Glass surfing is a relatively common behavior observed in Cory catfish. However, it is not considered a natural or essential activity for their well-being. It is important to try and identify the underlying cause and address any issues to ensure the overall health and happiness of the fish.

What temp should a tank be for Cory?

The ideal temperature for Corydoras (Cory) fish is between 72 to 78 degrees Fahrenheit. Maintaining a consistent temperature within this range promotes their health and well-being. A suitable environment is essential for adequately caring for these popular aquarium fish.


Understanding the reasons behind Cory catfish glass surfing is the first step toward creating a thriving aquarium environment. By addressing water quality issues, providing suitable hiding places, and ensuring a proper diet, Cory catfish can be kept happy and healthy in their aquarium. It is important to remember that every fish is unique and may have different needs, so observing the Corydoras glass surfing behavior and adjusting is vital. Overall, aquarists can create an optimal environment for these fascinating fish to thrive by understanding and meeting the specific needs of Cory catfish. 

You might also like

About Me

I am the founder of, a devoted wife and mother, and an avid fish enthusiast. My aim is to assist fellow fish lovers worldwide in understanding how to properly care for and breed their pet fish.

Recent Posts

Stay Updated

Get outdoor trends, data, new products, and tips delivered to your inbox.

error: Content is protected !!
Scroll to Top