How To Lower Ammonia In A Fish Tank Reduce Levels Naturally!

Estimated read time 16 min read

What Should I Do?

Follow these steps to reduce Ammonia in your fish tank;

  1. Immediately Do A Water Change
  2. Use A Gravel Vacuum
  3. Remove Any Uneaten Food
  4. Remove Dead Or Rotting Plants
  5. Remove Dead Fish
  6. Unclog Your Filter
  7. Cut Down On Feeding
  8. Make Sure Your Tank Isn’t Overstocked
  9. Use Chemicals (Band-Aids)
  10. Regular Partial Water Changes
  11. Continue to test your water and repeat until ammonia levels are acceptable.

Table of Contents

Ammonia And Your Fish Tank 

Ammonia is the most harmful toxin to your fish, and you need to get rid of it fast. 

You may be asking a few of the following questions:

  • How do I get rid of Ammonia in my fish tank naturally?
  • What causes high ammonia levels in a fish tank?
  • How to test water ammonia levels?
  • Why test water for Ammonia?
  • How to check your ammonia levels without a test kit?
  • What removes Ammonia from water?
  • How do I lower Ammonia in my fish tank without changing the water?
  • Does ammonia remover work in fish tanks?
  • How do you fix an ammonia spike?
  • Do fish tank filters remove Ammonia?

Below we will answer all these questions and even show you some other things you can do to help reduce Ammonia in your aquarium.

But first, let’s go into detail on what you should do if you have an ammonia problem.

Start by watching our video;

How to Get Rid of Ammonia in 10 Quick Steps:

If you have too much Ammonia, you should be worried, toxic Ammonia is the most harmful toxin for your fish, and it can kill them if you don’t fix it fast.

We will go into each step in more detail below, but first, check out this infographic to help you get a better understanding of the ammonia problem.

Infographic - How to Get Rid of Ammonia In Your Fish Tank
How to Get Rid of Ammonia In Your Fish Tank

Step 1) Immediately Do A Water Change

One of the first things you should do when you notice that your ammonia levels are high is to perform a 50% water change.

The water change won’t remove all the Ammonia, but it reduces the amount by adding clean water, allowing your biological filtration to catch up.

This is all part of the nitrogen cycle, and you can click here to see the 5 Fundamentals Of The Fish Tank Nitrogen Cycle explained in an easy-to-understand infographic.

Step 2) Use A Gravel Vacuum

Over time fish waste and uneaten food will accumulate in your gravel and start to produce Ammonia.

When you complete your water change, it’s a good time also to clean your gravel.

Now that you’ve completed a water change and cleaned your gravel, you need to identify the underlying symptoms of the Ammonia in your tank.

Usually, it’s one of the following items below.

Step 3) Remove Any Uneaten Food

Each time you feed your fish, remove any uneaten food floating around or any large chunks on the bottom of the tank.

Step 4) Remove Dead Or Rotting Plants

Just like fish waste, rotting plants will also produce Ammonia, so remove any dead or decaying plants as soon as you notice them.

Keep this in mind: If you have just set up a new aquarium, every new tank will have high levels of Ammonia at first; this is okay; it’s all part of the nitrogen cycle as bacteria is building in the filter media.

If you just set up your tank, the best thing to do is wait for your tank to cycle and avoid new tank syndrome.

Step 5) Remove Dead Fish

If you have a large community tank with lots of hiding places, it can be tough to notice dead fish.

But if you can’t keep your ammonia levels down, I suggest looking under some rocks; you never know what you might find.

Step 6) Unclog Your Filter

Your filter is one of the essential pieces of equipment in your tank. The filter is where your good beneficial bacteria will grow. This bacteria breaks down the Ammonia so your tank can cycle.

Suppose your filter is clogged, and water isn’t flowing freely over the bacteria. In that case, the Ammonia will not be broken down to less harmful nitrite levels, and you may experience an ammonia spike.

Check your filter tubes, cartridges, media, and impellers. If needed, clean your filter.

Step 7) Cut Down On Feeding

If you have an ammonia spike, your fish may become lethargic and likely not eat as much, take this time to cut down on feeding.

Try to feed your fish only once daily and ensure all the food has been eaten. Anything left behind will add to the ammonia levels.

Step 8) Make Sure Your Tank Isn’t Overstocked

Sometimes beginners will add too many fish too fast.

When you have too many fish, the bacteria that is building up in your tank has yet to establish itself and can’t keep up with the amount of waste produced by the fish.

Add fish slowly and allow your beneficial bacteria to develop over time.

Step 9) Use Chemicals (Band-Aids)

If you do all of the above and still have an ammonia problem, you can start to add chemicals and water conditioners like;

Another good product is Seachem AmGuard which can be used for emergencies and is suitable for up to 48 hours.

Remember that chemical fixes are only temporary, and you should still try to find the root of your ammonia problem.

It’s likely overfeeding, overcrowding, the biological filter has yet to develop, or your filter is clogged.

If you do all these things, you should start noticing an improvement within a day or two.

Step 10) Regular Partial Water Changes

If the problem persists, continue to perform water changes and the steps noted above until you notice an improvement.

Here is a quick video recapping the steps above.

How to Lower Ammonia in Your Fish Tank: A Comprehensive Guide

Maintaining a healthy ammonia level in your fish tank is crucial for aquatic life. High concentrations of ammonia can lead to health problems for your tropical fish and disrupt the aquarium nitrogen cycle. In this comprehensive guide, we will explore effective ways to lower ammonia levels and create a healthy environment for your aquatic companions. Let’s dive in!

Understanding Ammonia

Ammonia (NH3) is a chemical compound that can be harmful in excess. It is primarily produced by fish as a natural waste product, contributing to the water column’s ammonia content.

Detecting Ammonia Levels

Regular water testing is the first thing every fish keeper should do. Use a water test kit to measure ammonia readings and ensure your tank stays within safe levels. This practice will help you identify high concentrations of ammonia early on.

Causes of Ammonia Buildup

Several factors can lead to ammonia buildup in your tank, including leftover food and uneaten fish foodDead plants and excess organic matter can also contribute, as can overcrowding and maintaining too many fish. Insufficient filtration systems and new fish tank syndrome may worsen the problem.

The Impact of Ammonia on Fish and Aquatic Life

High ammonia levels can have severe consequences. It can cause health problems in fish, affecting their well-being. Additionally, it can disrupt oxygen levels in the water, impacting other aquatic life within the tank and compromising the aquarium ecosystem.

Effective Ways to Lower Ammonia Levels

A. The first step: Conducting a partial water change

One of the most effective ways to combat ammonia is by performing a partial water change. This process involves removing a portion of your fish tank’s water, which helps dilute the amount of ammonia present.

B. Performing a large water change in extreme cases

In severe cases with extreme ammonia levels, consider a drastic water change to quickly reduce the ammonia concentration.

C. Using water conditioner to detoxify ammonia

Water conditioners can be a temporary solution to neutralize ammonia and make it less harmful to your fish until more permanent measures can be taken.

D. Activated carbon filter as a great way to remove ammonia

Investing in an activated carbon filter is a great way to eliminate ammonia from your tank. The filter’s porous structure provides ample surface area for beneficial bacterial growth, which helps in ammonia removal.

E. Introduction of healthy bacteria through live rock

Live rock in saltwater aquariums is an excellent source of healthy bacteria that can aid in reducing ammonia levels. These bacteria play a crucial role in the aquarium nitrogen cycle.

F. The role of an air stone in improving oxygen levels

Increasing oxygen levels with an air stone can help your fish cope with the effects of ammonia exposure and promote overall tank health.

G. Temporary solutions for immediate relief

In extreme cases, you can consider using chemical compounds designed to lower ammonia levels temporarily. However, these should only be viewed as a stopgap measure.

Preventing Ammonia Buildup

A. Feeding your fish in moderation and removing excess food

Moderate feeding and removing uneaten fish food will reduce the amount of ammonia introduced into the tank.

B. Maintaining a clean and healthy environment

Regular water changes and cleaning dead plants and organic matter from the tank will contribute to a healthy environment.

C. Choosing the right filtration system for your tank

Select an appropriate filtration system that can handle the biological load of your tank to prevent ammonia buildup.

D. Ensuring a balanced fish-to-water ratio

Avoid overcrowding your tank and maintain a balanced fish-to-water ratio to reduce ammonia production.

E. Regular water changes as a proactive measure

Regular water changes are the easiest way to maintain safe ammonia levels and create a healthy environment for your fish.

F. Monitoring ammonia levels as part of routine maintenance

Incorporate ammonia testing into your routine maintenance to catch and address issues early.


In conclusion, lowering ammonia levels in your fish tank is essential for creating a safe and thriving aquatic environment. By understanding the causes of ammonia buildup and implementing effective methods to combat it, you can ensure the well-being of your fish. Remember to practice responsible fish keeping and prioritize the health of your aquatic companions.

What causes high ammonia levels in a fish tank?

The most common way Ammonia enters your fish tank is from tap water, fish waste, uneaten food, and when things like live plants die and decompose.

Source: Aquarium Water Quality: Nitrogen Cycle. Florida Department Of Agriculture And Consumer Services, 2020.

How to test water ammonia levels?

You can quickly test your water for Ammonia using a test kit like this one from API.

There are simple test strips you can use as well. However, these test strips are less accurate than the water test kits, but they can give you a quick idea.

Why test water for Ammonia?

Testing for Ammonia is crucial because it’s not something you can see with your eye.

Ammonia is toxic and can harm your fish when present in your aquarium. The earlier you know about it, the faster you can correct it.

How to check your ammonia levels without a test kit?

If you don’t have a test kit, you can check for ammonia levels by looking at your fish for signs of ammonia poisoning.

If you notice;

  • Loss of appetite
  • Lethargy
  • Damage to their gills
  • Or signs of Stress

This could be an indication of ammonia poisoning.

If you notice these signs, the best thing to do is get a test to confirm the exact levels and take the steps noted above to lower the Ammonia in your tank immediately.

Also, most aquarium stores will test your water for free. But if you have a tank, you should have your own, and the API Master Test Kit is relatively inexpensive and very reliable.

What removes Ammonia from water?

The beneficial bacteria growing around your aquarium break down the Ammonia into less harmful toxins that are further broken down into nitrites.

This is all part of the nitrogen cycle.

Additionally, live plants in your aquarium will use the Ammonia as food during photosynthesis which helps keep ammonia levels lower.

We always recommend having a few live plants in every aquarium.

How do I lower Ammonia in my fish tank without changing the water?

Keep Your Ammonia Levels Lower Through Prevention!

If you’ve completed all the above steps, you’ve removed or at least lowered the ammonia levels in your tank.

Since you don’t want to go through all this work for the second time, you need to monitor your water parameters by testing your water weekly with an aquarium test kit.

As you use your test kit, it’s essential to understand that you are hoping for an ammonia level near 0; this may only sometimes be possible as your fish continually produce waste.

You can use a nifty chart on that shows you when Ammonia will become toxic to your fish, depending on your PH level and temperature.

When you check out the chart, one necessary takeaway is that the warmer your water is, the less Ammonia it takes to become toxic to your fish.

Prevention is all part of the bigger picture in maintaining your aquarium and regular cleaning schedule. Everyone should read this article on cleaning an aquarium.

Does ammonia remover work?

Ammonia removal products will work, but only temporarily.

They won’t address the root of the problem, causing your ammonia levels to spike.

I recommend using ammonia removers only when setting up a new tank, when you have an overstocked tank or when you first notice an ammonia spike but can’t do one of the seven steps listed above.

How do you fix an ammonia spike?

An ammonia spike is typically caused by a build-up of fish waste, uneaten food, and when aquatic plants die and decompose.

When dealing with an ammonia spike, you should look for things like dead fish, rotting plants, uneaten food, or possibly a clogged filter.

Remove any decaying organic matter that you find immediately.

Different types of media you use in your fish tank filter can help remove and lower the ammonia levels in your fish tank.

That said, your filter media is not removing the Ammonia but converting it into less harmful nitrates.

Nitrifying Bacteria, Nitrosomonas, found in your filter media and everywhere in your tank, consume Ammonia and convert it into Nitrites.

Learn More: Read our full article on some of the best nitrifying bacteria you could use in your aquarium.

Do fish tank filters remove Ammonia?

The filter itself doesn’t remove Ammonia from your fish tank.

Instead, the bacteria growing on the biological media in your filter remove the Ammonia from your water.

This is why it’s essential to wait a few days before adding fish to a new aquarium; your beneficial bacteria need time to grow on the media to make the filter useful.

It’s important to understand that a well-established aquarium grows beneficial bacteria everywhere.

The gravel, plants, and decor all provide a place for this beneficial bacteria to grow, and it is quite possible not to use a filter at all and still have a well-balanced aquarium.

Final Thoughts

Suppose you try the above steps and still have an ammonia issue.

In that case;

The products listed below help reduce Ammonia and come in pellets, neutralizing drops, and even media for your filter.

  1. Best way to remove ammonia from a fish tank: Python Water Changer
  2. Best ammonia remover for fish tank: API AMMO-LOCK
  3. Best ammonia-removing filter media: Fluval Ammonia Remover

Further Reading: Do You Have More Problems? We Put Together A List Of The Most Common Aquarium Problems Along With Their Causes And How You Can Fix Each Problem.

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