Cory catfish are the most common bottom dweller fish aquarists prefer to add to their home aquarium because of their peaceful and hardy nature. They can live in a wide range of water parameters and conditions.
Sometimes beginners ask if we can keep a bottom dweller fish without a filter. So, Can cory catfish live without a filter? So, let us find out.
Cory catfish cannot live without a filter as they are freshwater fish and require clean water conditions to thrive. A filter helps keep the water clean and protected from harmful toxins like ammonia. Your cory catfish tank’s water chemistry will remain balanced with a good filtration system.
This article will discuss whether cory catfish can live without a filter and how we can keep them without a filter. So, let us get into it and find every answer to your questions.
- 1 Do cory catfish require a filter in their aquarium?
- 2 What are the Ideal water conditions cory catfish require to thrive?
- 3 Which is the best filter for my cory catfish tank?
- 4 How long can a cory catfish survive without a filter?
- 5 How can I keep my cory catfish without a filter?
- 6 Conclusion:
Do cory catfish require a filter in their aquarium?
Cory catfish do require a filter in their aquarium.
They are tropical freshwater fish that lives in clean water conditions.
Cory catfish will require clean water to thrive and ensure their longer lifespan.
Keeping your cory catfish in a tank without a filter can come with various issues.
Even after performing a water change, you will not be able to keep the water clean as it is in a tank with a well filtration system.
Filter helps in protecting the water from harmful toxins like ammonia and nitrite.
Using biofilter media in your filter will eliminate the ammonia and nitrite from your aquarium.
The high ammonia level will result in burning your cory catfish skin, gills, and body, making them come into critical condition, and even they can pass away.
So, consider adding a good filtration system to your cory catfish tank to ensure clean water conditions.
Also read: Do Cory Catfish Need Oxygen?
What are the Ideal water conditions cory catfish require to thrive?
Cory catfish require clean water conditions to thrive.
Good water quality will help ensure your cory catfish’s good health and longer lifespan.
To ensure good water conditions, perform a weekly water change of at least 35% to keep the water clean.
Treat the water with a water conditioner when performing a water change to dechlorinate it as chlorine can affect your cory catfish health.
We recommend using the API water conditioner to treat the water as it eliminates chlorine, chloramine, heavy metals, and harmful toxins like ammonia and nitrite from the water.
Add a good filtration system with biofilter media to keep the water clean and protected from harmful toxins like ammonia and nitrite.
Keep a regular check on ammonia, nitrite, and nitrate levels and ensure to maintain the ammonia and nitrite at 0ppm, whereas nitrate at below 20ppm.
We recommend using the API master test kit to check ammonia, nitrite, and nitrate levels regularly.
Also, this kit will help you check the pH level of your cory catfish tank.
You can buy it from amazon: API FRESHWATER MASTER TEST KIT.
Also, adding plenty of live aquatic plants will keep the water clean by absorbing carbon dioxide.
Live aquatic plants will keep your cory catfish tank well oxygenated.
It is essential to keep our tank well oxygenated.
You must know that the beneficial bacteria present in our aquarium require oxygen to break down harmful toxins like ammonia and nitrite.
So, consider adding an air pump to your cory catfish tank and also add plenty of live aquatic plants.
Also read: Ideal pH Level For Cory Catfish?
Which is the best filter for my cory catfish tank?
These are different types of filters you can add to your cory catfish tank:
- Internal filter
- Cannister filter
- Hob filter
An internal filter needs to get placed inside your cory catfish tank.
It will eat up a lot of space in your cory catfish tank.
So, it isn’t the best choice to add to your cory catfish tank.
A canister filter is the best option you can go for as it will be placed beneath the aquarium and will also keep the water super clean and safe from harmful toxins like ammonia and nitrite.
Add biofilter media to your canister filter, and they are ready to go.
You can purchase it from Amazon Fluval High Performance Aquarium Filter.
You can also go for a hob filter as it is easily affordable and will be placed at the back of the tank, not consuming the space.
However, it will not provide all benefits and comes with fewer benefits.
They are good for a small tank, but we recommend using a canister filter for a big-size tank.
How long can a cory catfish survive without a filter?
Cory catfish will not be able to survive long in dirty water conditions.
They will survive for 6-8 days without a filter, with a minimum of 3-4 days.
We don’t recommend keeping your cory catfish or any other fish without a filter as it can make them suffer from life-threatening conditions because of bad water conditions.
A filter protects the water from harmful toxins like ammonia and nitrite.
Ammonia and nitrite can cause the critical condition to your cory catfish health.
Living in dirty water conditions, your cory catfish will come under high-level stress and become prone to various diseases and parasites.
How can I keep my cory catfish without a filter?
You should not keep your cory catfish without a filter.
However, if you have made your mind to keep your cory catfish without a filter, you have to ensure all these things:
- Cycle the tank without adding fish.
- Perform a more frequent water change than regular.
- Add plenty of live aquatic plants.
- Add an air pump to your cory catfish tank.
- Keep your cory catfish in a large size tank.
- Avoid overcrowding your cory catfish tank.
- Use a special substrate for your cory catfish tank.
- Perform regular maintenance of your cory catfish tank.
Perform a nitrogen cycle
Performing a nitrogen cycle is essential for creating a balanced ecosystem for your cory catfish.
When you don’t use a filter, it is essential to perform a nitrogen cycle.
A nitrogen cycle is necessary because it will create good beneficial bacteria in your cory catfish tank, which will feed on and break down harmful toxins into less harmful components.
It is a very easy process that demands only your time and patience.
It takes time to cycle your tank, but once it is cycled, you are ready to add your fish to the tank.
Make sure that there is no presence of any fish in the tank while performing a nitrogen cycle.
Follow these steps to perform a nitrogen cycle:
- Treat the tap water with a water conditioner and fill it in your tank.
- Add a small amount of fish food to your tank until you see the ammonia spike in your tank.
- Continue adding small amounts of food and keep looking for nitrites.
- You will be able to detect nitrites as the beneficial bacteria will start breaking down the ammonia into nitrites.
- Now, keep monitoring for nitrates, as when the ammonia and nitrite get eliminated from the tank, nitrates will appear.
- When the ammonia and nitrite stand at 0ppm, the nitrogen cycle is completed, and you can now start adding your cory catfish.
Make sure to keep the nitrate level below 20ppm; above these nitrate levels, your cory catfish health will be affected.
Performing a regular water change and tank maintenance will help you balance the water chemistry of your cory catfish tank.
Perform a more frequent water change
We recommend performing a weekly water change of at least 35% when having a filter.
Without a filter, you must do a more major water change of 50-60% more often.
It all depends on how fast your tank is getting polluted with waste and leftovers.
You must perform a water change whenever you see much waste and leftovers in your cory catfish tank.
However, you will not be able to perform more often water change which is why we recommend using a filter.
Add live aquatic plants.
Adding plenty of live aquatic plants to your cory catfish tank will help you keep the water clean.
Plants will use the toxins released from the waste products and release oxygen in the water, making the tank well oxygenated.
It will also help boost the nitrogen cycle if you add them in the beginning.
Add an air pump
Usually, an air pump helps create the movement in the water surface for the oxygen exchange.
The filter also creates movement, but the air pump will do the work when there is no filter.
Lack of oxygen in a tank will result in cory catfish having trouble breathing and coming under stress.
Also, with a lack of oxygen in a tank, beneficial bacteria will not be able to break down harmful toxins like ammonia and nitrite.
Also, no movement in the water surface will result in surface scum.
Keep your cory catfish in a large size tank.
The small-size tank will get dirty soon, and also, the parameters will not be stable because of the low volume of water.
There will be an anytime risk of ammonia spike because of fish waste and other organic wastes.
So, keeping your cory catfish in a small tank in the absence of a filter will not be a good idea.
However, an ideal tank requirement of a cory catfish is 20-gallon.
So, it would help if you consider at least keeping your cory catfish in a 30-gallon tank when not using a filter.
Also read: How Many Cory Catfish In A 10 Gallon Tank?
Avoid overcrowding your cory catfish tank.
An overcrowded tank will come with all these issues:
- The crowded tank will become polluted faster than regular.
- An overcrowded tank will lack oxygen.
- The crowded tank will have a risk of ammonia spike because of excess waste.
- All your fish will not be able to live and swim comfortably.
And when you keep your cory catfish tank overcrowded, without a filter, the water conditions of the tank will not be less than a disaster for them.
So, to ensure that you are not overcrowding your cory catfish tank, follow the one-inch one-gallon rule, which is one inch of fish per gallon of water.
Cory catfish are 2-2.5 inches long on average, and some species can be as long as 4 inches in size.
They are schooling fish and prefer to live in a large group of at least 5-6.
So, a 20-gallon tank is the ideal tank size for them, but without a filter, consider keeping them in a 30- gallon tank.
Use a special substrate.
Going for the right substrate is essential to keep the water conditions clean without using a filter.
When adding live aquatic plants, you must use a substrate that will hold the nutrients your plants will use to grow.
Using gravel or sand will not hold such nutrients and are also difficult to clean.
We recommend using ADA Aquasoil Amazonia as it holds nutrients and is easy to clean.
Perform regular maintenance of your cory catfish tank
Regular maintenance of a tank is essential even when you have a filter.
So, it becomes more essential without a filter.
Clean your aquarium glass and substrate weekly and siphon out all the leftovers and debris using a gravel siphon.
The necessity of water will depend on how fast the water is getting polluted by toxins and waste.
However, if you have to change the water every other day, we recommend adding a filter.
Cory catfish cannot live without a filter as they are freshwater fish and require clean water conditions to thrive.
Adding a filter with biofilter media will help you keep the water clean and protected from harmful toxins like ammonia and nitrite.
However, if you have decided to keep cory catfish in a tank without a filter, then there are some things you should ensure to keep your cory catfish safe.
Perform a more frequent water change of 50-60%, add live plants, use special substrate, run a nitrogen cycle, add an air pump, and avoid overcrowding your cory catfish tank.
However, we don’t recommend keeping your cory catfish without a filter as it can make them suffer from various issues like stress, diseases, and parasites.
If you have to do a water change every next day, just add a filter as it is very much required in that tank.