Do Betta Fish Need a Cycled Tank?: What You Need To Know

Betta fish are popular aquarium fish pets because of their bright colors and flowing fins.

These tropical fish have few health problems with proper care.

Maintaining a clean aquarium goes a long way in preventing betta illnesses.

Establishing a nitrogen cycle can make tank maintenance much easier.

But do betta fish need a cycled tank?

A cycled tank is a crucial part of a betta’s habitat. The nitrogen cycle breaks down harmful toxins like ammonia and nitrite. Without an established nitrogen cycle, it is difficult to maintain stable water parameters. Placing a betta in an uncycled tank puts the fish at risk for severe illness.

do betta fish need a cycled tank atf

What Is a Cycled Tank?

A cycled tank means a complete nitrogen cycle is already established.

A nitrogen cycle’s purpose is to convert and remove harmful toxins like ammonia and nitrite.

Fish waste and leftover betta food produce these toxins as they break down in the substrate.

If you have an uncycled tank, toxin levels fluctuate regularly. The unstable environment becomes very unsafe for your betta.

In a cycled tank, beneficial bacteria feed on the toxins and convert them to less harmful substances. This results in more stable water parameters.

Stable water conditions create a healthier environment for your betta. Poor water quality is the main cause of many common betta diseases like fin rot and swim bladder disorder.

How Does the Nitrogen Cycle Work?

The nitrogen cycle is an invisible three-stage process of converting ammonia into nitrite. Nitrite is then converted to less-harmful nitrate.

There are two methods of establishing a nitrogen cycle: fishless cycling and fish-in cycling. Both methods achieve the same goal, but you do fish-in cycling with your betta in the tank.

A fish-in cycle works in an emergency, but it is not recommended. Establishing a nitrogen cycle with your betta in the tank can harm your fish.

Doing a fishless cycle is the best way of starting a nitrogen cycle in your aquarium.

Before beginning the nitrogen cycle process, have your tank completely set up with your heater and filter running.

Start by checking your water parameters with an aquarium testing kit. Knowing your pH levels and water hardness helps with the process.

High or low pH levels prevent beneficial bacteria from reproducing. Aim for a pH level close to 7.0, which is neutral.

You must also check your water temperatures. Everything must measure to the same levels you would have with your betta fish.

Ideal temperatures for bettas range from 78-80° degrees Fahrenheit (25.5-27° C). This is also a good temperature range for the growth of beneficial bacteria.

Treat your aquarium with a water conditioner. This removes chlorine, which can kill the beneficial bacteria you will establish.

Once you establish baseline measurements for your water parameters, you may start the cycling process.

The entire cycling process takes several weeks to complete. This period of time depends on your tank size and how fast the helpful bacteria multiply.

Add Ammonia to Your Tank

ammonia cycle betta

Adding ammonia to your tank is the first step in creating a nitrogen cycle. Ammonia feeds beneficial bacteria and starts the cycling process.

Beneficial bacteria appear without intervention in fish tanks. There is little evidence to suggest adding beneficial bacteria from an already cycled tank speeds up the process.

Use ammonia with the ingredients listed as ammonia hydroxide and water. Do not use ammonia with dyes or other chemical additives in the ingredients.

Add 3-5 drops of ammonia for every gallon of water. Wait a few minutes and test your ammonia levels.

Keep adding ammonia until your tests measure ammonia levels of 2 ppm (parts per million).

Maintain Ammonia Levels

As the beneficial bacteria multiply, they consume the ammonia and break it down.

Keep testing your water parameters for ammonia and nitrite levels.

Repeat the previous step of adding ammonia to the tank when levels get below 2 ppm.

After 1-2 weeks, the beneficial bacteria will convert ammonia into nitrite. It will start showing up in your water parameter tests.

When your tests show measurable nitrite levels, this signals the progression of the nitrogen cycle.

Nitrates Appear

Over time, ammonia levels drop, and nitrite levels rise.

Beneficial nitrifying bacteria begin converting nitrite into less harmful nitrate.

Nitrate levels are usually measurable after 3-4 weeks.

Your tank is completely cycled when ammonia and nitrite levels measure 0 ppm, and there are measurable nitrate levels.

Performing weekly partial water changes keeps nitrates safe for your betta.

For more details on changing betta water, check out our guide here.

What Are the Dangers of Ammonia and Nitrite?

nitrite in betta cycled tanks

Ammonia and nitrite are very toxic to betta fish.

Anything over 0 ppm of ammonia can harm your betta’s health.

Nitrite levels should also remain at 0 ppm.

Signs of ammonia or nitrite toxicity in your betta include:

  • Loss of appetite
  • Lethargy
  • Ammonia burns
  • Gasping for air at the surface
  • Rapid gill movement
  • Gill discoloration
  • Staying near the filter
  • Erratic swimming movements

If you see these symptoms in your betta, immediately perform a partial water change. Your tank may need more frequent water changes until ammonia and nitrite levels return to 0 ppm.

Ammonia poisoning is not common unless you are not cleaning your tank every week. It is also common in overstocked tanks.

Excess ammonia build-up comes from fish waste, leftover food, and dead plants.

If your tank has high ammonia levels, there is more ammonia than your beneficial bacteria can process.

What Role Does Nitrate Have in a Cycled Tank?

Live aquatic plants consume nitrate as a fertilizer. Nitrate also increases algae growth.

High nitrate levels deplete oxygen in the water.

If your betta gets exposed to high nitrate levels for long periods, it can suffocate.

Nitrate is not as toxic to bettas as ammonia or nitrite. Trace amounts of nitrates are safe for betta fish.

Aim for nitrate levels less than 40 ppm. Keep nitrates at safe levels with weekly partial water changes.

How Do You Establish Beneficial Bacteria Colonies?

You do not have to add beneficial bacteria to your fish tank. They already exist there as a part of nature.

Beneficial bacteria live in your substrate, plants, and your filter media.

Establish beneficial bacteria colonies by adding ammonia to the water.

As the bacteria feed on the ammonia, they multiply and convert ammonia into nitrite.

This is where a new batch of bacteria comes in, known as nitrifying bacteria.

Nitrifying bacteria feed on nitrites and convert them to nitrates.

Fish waste, leftover food, and dead plant life produce ammonia in a cycled tank.

The beneficial bacteria continue feeding on the ammonia and multiplying. This keeps the nitrogen cycle process going.

How Often Should You Test Water Parameters in a Betta Tank?

check water cycled tank betta

I recommend testing your water parameters in your betta tank every week.

This lets you stay on top of small changes before they become bigger issues.

If you wait to test your water after your betta gets sick, the issue is more challenging to remedy.

Now you not only have to fix your water parameters but treat your betta for illness as well.

Most aquarium testing kits measure pH, ammonia, nitrite, and nitrate levels.

Test tube kits offer more accuracy than testing strips.

Read more on this in our massive guide to the proper betta water parameters.

How Often Should You Perform Water Changes in a Betta Tank?

Perform partial water changes once per week.

Remove only 20-25% of your tank water at one time.

Taking out too much water can remove too much of your beneficial bacteria. This causes your nitrogen cycle to crash until you establish a larger colony of beneficial bacteria.

As you remove water from the tank, clean the substrate with a gravel vacuum and scrape algae from the sides of the tank.

Fill a clean bucket with the same amount of water you removed from the tank.

If you are using tap water, treat it with a water conditioner. Aquarium water conditioners remove harmful chlorine, chloramine, and heavy metals.

Chlorine can kill your beneficial bacteria as well as your betta fish.

Stir in the water conditioner and allow it to sit for a few minutes.

Ensure the water is close to the same temperature as the tank water. This prevents sudden temperature fluctuations in your betta tank.

Go slow when pouring the water back into the tank. Many fish owners pour the water over a small plate to avoid disturbing the water too much.

Let the water settle for about an hour, and test your water parameters.

Do You Need a Filter in a Betta Tank?

The nitrogen cycle doesn’t remove all the bacteria from your tank water. Issues with water quality are the main cause of most betta diseases.

An aquarium filter removes harmful bacteria and circulates the water. Beneficial bacteria colonies also establish themselves in your filter media.

When cleaning your tank, rinse the filter media in old tank water to remove debris. Rinsing filter media in tap water can destroy beneficial bacteria and introduce chlorine into the tank.

Bettas cannot swim well in fast currents.

Choose a sponge filter with a low-flow setting for your betta.

Your filter should circulate all the water in your tank 4-6 times per hour. This is the filter rating, which is usually labeled as GPH (gallons per hour).

For a 10-gallon tank, choose a filter rated at 40-60 GPH.

Do You Need a Heater in a Betta Tank?

Bettas are tropical fish, so they need warm water temperatures. Low temperatures cause poor digestion in bettas, leading to other health issues.

You need an aquarium heater to maintain the correct temperatures for your betta.

The ideal temperature range for bettas is 78-80° degrees Fahrenheit (25.5-27° C).

Warm temperatures also encourage the development of beneficial bacteria.

A quality aquarium heater should produce 3-5 watts for every gallon of water.

In a 10-gallon tank, you need a 30-50 watt heater.

Placing the heater near the filter helps circulate the water throughout the tank.

What Type of Substrate is Suitable for a Betta Tank?

substrate for betta cycled tank

The most common substrate in betta tanks is aquarium gravel. Ensure the gravel pieces are small and smooth, so they do not tear your betta’s fins.

A lot of your beneficial bacteria colonies live underneath the gravel substrate.

You may use sand as a substrate, but it is difficult to clean and does not support live plants properly.

Avoid coral sand, as it may also leach calcium into the water. Calcium can increase water hardness and make some compounds more toxic.

Copper, lead, and zinc become even more toxic when combined with calcium.

Some live plants need nutrient-rich soil to thrive. Aquarium soil can create a mess and is difficult to clean.

Adding a thin layer of aquarium gravel over the soil makes cleaning easier.

Should You Have Live Plants in a Betta Tank?

Aquatic plants add visual interest and create a natural environment for your betta. Plants provide your betta with hiding spots and places to explore.

Live plants also feed on nitrates and help maintain stable water conditions.

Some excellent live plant options for bettas include:

  • Amazon sword
  • Anubias
  • Java moss
  • Brazilian pennywort

Fake plants offer the same benefits as live plants, but they are still a nice addition to a betta tank.

Avoid plastic plants because they may have sharp edges and tear your betta’s fins.

Instead, choose artificial plants made of silk. Silk is soft and smooth and will not injure your fish.

Don’t Crash the Nitrogen Cycle in Your Betta Tank!

Establishing a nitrogen cycle is important in setting up your betta tank.

The nitrogen cycle helps remove harmful toxins and creates a healthier environment for your betta.

Stay on top of testing your water parameters and correct any issues if they occur.

If you are unsure how to get your water parameters back on track, consult an aquarium specialist. They can point you in the right direction so you do not worsen the problem.

To set up your water the right way, you need water conditioners.

Check out our reviews on the best betta water conditioners to give your pet the healthiest home possible and also our post on the signs of a cycled aquarium.

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Toni Tedescucci is a freelance writer who loves all animals, especially betta fish. When she isn’t busy writing for Betta Fish Bay, she’s spending time with her family or getting cozy with her cats and a good book.

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