Ammonia in Shrimp Tanks

Ammonia in Shrimp Tanks

Ammonia is a nitrogen compound that occurs naturally in any shrimp aquarium. It is the resulting waste product of the animals. It also accumulates in the water column from the decomposition of undigested food, excess feed, and other organic wastes.

Ammonia is very toxic to dwarf shrimp. Even at relatively low concentrations, it affects various aspects of shrimp health.

So, what is ammonia? What causes it in our tanks? How it affects dwarf shrimp? What are the symptoms of ammonia poisoning in shrimp? You will find answers to these and many other questions here. 

Without further ado let’s get started.

1. What is Ammonia?

Ammonia is a colorless gas with a sharp and penetrating odor. The ammonia molecule has 3 hydrogen atoms and an unshared pair of electrons attached to the nitrogen atom. 

Ammonia gas can be easily dissolved in water. In science, this kind of ammonia is called liquid ammonia or aqueous ammonia. Once exposed to open air, it quickly turns into a gas once again. 

Ammonia occurs naturally and is produced by shrimp activity when food (proteins and amino acids) are broken down in the body. It is the major end-product of protein catabolism in animals.

2. Forms of Ammonia in the Tanks

Ammonia in Shrimp Tanks - forms of ammoniaIn the water, ammonia has two primary forms:

  1. ionized (NH4+) and
  2. un-ionized (NH3),

Note: These two forms of ammonia are always in equilibrium which plays a huge role in our aquariums. I will be talking about it a little bit later.

The un-ionized form is particularly harmful to aquatic animals because it can easily diffuse across cell membranes and is highly lipid-soluble. It is many times more toxic than the ionized form.

3. What Causes Ammonia Buildup?

Ammonia is one of the most common water quality problems. However, before we treat the problem we need to understand how it happens in the first place.

Here are some possible reasons how ammonia can build up in our tanks:

3.1. A new set-up (or unfinished nitrogen cycle)

During this stage, new tanks do not have enough waste to keep the colony of beneficial bacteria in the filter or it could be that the bacteria colony is not large enough for the added bioload.

3.2. Overfeeding

Uneaten and decaying foods are some of the largest sources of ammonia in a shrimp tank. We all love to feed our pets. Unfortunately, it can easily lead to overfeeding without perhaps realizing it.

3.3. Overdosing medications

Medication we use to treat our shrimp can often damage a biological filter resulting in elevated ammonia levels.

3.4. Insufficient filtration

Power outage, substrate change, filter exchange, or over-cleaning your filtration, etc. can also cause ammonia spikes.

3.4. Inappropriate maintenance

Leftovers, decaying plants, and leaves, inadequate use of plant fertilizers, using untreated tap water, etc.

Have you noticed anything in common?

Yes, in most cases it is all about the amount of beneficial bacteria compared to the existing bioload (in other words, ammonia) in the tank.

Our tanks are self-contained ecosystems. Therefore, they heavily rely on beneficial bacteria to break down ammonia to nitrites (less toxic) and nitrates.

4. How Ammonia Affects Shrimp

Ammonia poisoning can be detrimental to the shrimp. It is irritating and corrosive. Ammonia toxicity has various deleterious acute and chronic effects on the dwarf shrimp, such as:

4.1. Stress

Ammonia causes a lot of stress for your shrimp. It affects their immune system and makes them susceptible to parasites and other diseases including bacterial infections, fungal infections, or all types of different illnesses.

You can also read my articles

4.2. Reduced Feeding Rates

Ammonia can damage their digestive tract by changing intestinal metabolism. It prevents shrimp from eating properly and also leads to poor nutrient absorption.

It can also cause significant damage to the intestines, accompanied by necrosis.

Eventually, shrimp stop eating, become weaker and die.

4.3. Growth Reduction

Ammonia negatively influences shrimp’s growth. Basically, a combination of shock and inappropriate feeding stuns their growth rate. 

4.4. Respiration problems

In shrimp, ammonia is also associated with hypoxia.

Shrimp gills are in constant contact with the external environment. Therefore, they are directly affected by environmental factors such as ammonia. Most studies have shown that even the smallest amount of ammonia may cause gill damage in shrimp.

It enters into their bloodstream and binds hemocyanin cells (these are the oxygen-carrying vessels of the shrimp’s body). Systematic exposure to ammonia will suffocate shrimp.

4.5. Molting and Metabolism Changes

According to some experiments, during the ammonia exposure, the inter-molt period of the invertebrates was shortened between molts.

It would not be an exaggeration if I say that molting is the most stressful and important physiological process in a shrimp’s life. Being unprepared for a molt is the worst that can happen with them.

According to another study, molting is strongly impacted by high ammonia levels, as the epidermis-secreted chitinase degrades the inner layers of the old exoskeleton to synthesize a new one during molting (ecdysis) has been shown to be significantly decreased in shrimp upon ammonia stress treatment.

Exposure to ammonia can disturb amino acid metabolism, by increasing the expression of some genes related to ammonia detoxification and excretion.

A high concentration of ammonia destroys the excretory system and osmotic balance in the shrimp.

As a result of these physiological and immune impacts, eventually, ammonia leads to mortality in shrimp tanks.

6. Common Symptoms of Ammonia Poisoning

Ammonia is a silent killer. So, how do you tell if there is too much ammonia in the shrimp tank?

Unfortunately, in shrimp, the early signs of ammonia stress are not easy to detect visually, even if you are paying attention to your shrimp regularly. Once you see the listed below symptoms, it means that ammonia concentration is already too high. 

  1. At first, they may quickly respond in the form of increased movement or abnormal swimming behavior. You can notice that your shrimp start rushing feverishly around the tank from corner to corner.
  2. After some time shrimp become lethargic. Probably due to prolonged exposure to ammonia. Eventually, they stop moving.
  3. They do not seem to be able to stand up or grip anything.
  4. Reduced appetite. They stop eating.
  5. Because of the ammonia stress, shrimp can lose color.

Unlike fish, shrimp do not have clear symptoms like:

  • gasping for air at the surface of the tank water.
  • their gills do not start bleeding or become red/purple.
  • inflamed eyes or anus.

7. What Affects Ammonia Toxicity?

In our aquariums, the toxicity of ammonia is affected by factors including:

  • pH,
  • temperature,
  • alkalinity,
  • dissolved oxygen, and
  • salinity.

Any changes in these factors will give rise to fluctuations in ammonia concentration in water.

7.1. pH and Ammonia

Ammonia is more toxic to shrimp at higher pH levels.

In order to understand how ammonia and pH correlate, I have to be more technical. However, I will try to keep it very short and simple.

Do you remember me mentioning two forms of ammonia (ionized (NH4+) and un-ionized (NH3)) in the water? In water, unionized ammonia exists in equilibrium with ammonium ion and hydroxide ion. 

NH4+=NH3+ H+

which may also be written as

NH4++ OH = NH3+ H2O

Basically, there is a ratio of 1:1 between ammonia and ammonium when the pH is around 9.25. Chemically, when your pH changes it will also change the ratio. In other words:

  • when the pH is low (pH <8.75) ammonia mainly exists in the form of NH4+ (toxic in high concentrations);
  • when the pH is high (pH >9.75) ammonia mainly exists in the form of NH3 (very toxic).

How pH affect ammonia in aquariumsNow some of you may say, well, our tanks usually do not have even pH 8.7. So, why should it bother us?

Well, it should!

Because the pH values are represented on a logarithmic scale, it means each pH value is 10 times more acidic than the next value. 

For example, the toxicity of ammonia is several times more severe at a pH of 8.0 than it is at pH 7.0. Obviously, it is also more dangerous at pH 7.0 than it is at pH 6.0, and so on. Even these concentrations are dangerous to shrimp.

Depending on the pH levels, the same concentration of ammonia can be safe or dangerous for the shrimp! Therefore, it would NOT be correct to say that levels of ammonia (up to 0.03 mg/1 (or ppm)) or less are not harmful to shrimp.

7.2. Temperature and Ammonia

How temperature affect ammonia in aquariumsAccording to the studies, the activity of ammonia in the water is much lower at low temperatures and higher at warm temperatures.

At low temperatures and low pH, the activity as NH3 is even lower, and as NH4+ is even higher.

As a result, even sensitive aquatic animals (like dwarf shrimp) can tolerate a higher level of ammonia at low temperatures than at high temperatures because of the less NH3 being present in the tank water.

7.3. Dissolved Oxygen and Ammonia

Dissolved oxygen and alkalinity also play a crucial role in shrimp tanks.

Even though there is no direct correlation between them and ammonia, they are also fundamental in the removal of ammonia via the aerobic nitrification processes.

Nitrification is the process that converts ammonia to nitrite and then to nitrate. Nitrifying bacteria (Nitrosomonas bacteria) convert ammonia into nitrite.

It is been demonstrated that nitrification rates will exist if dissolved oxygen levels exceed 5 milligrams (or 5 ppm). Low levels of aeration in tanks can easily cause ammonia build-up to reach toxic levels.

7.4. Alkalinity and Ammonia

In shrimp tanks, the increase in ammonia can also be caused by the fluctuation of pH levels, which is caused by low alkalinity.

For every mg/L of converted ammonia, alkalinity will decrease by 7.14 mg/L. Therefore, alkalinity should be at least 8 times the concentration of ammonia present in the aquarium. Otherwise, this could result in an incomplete nitrification process.

7.5. Salinity and Ammonia

According to the experiments, increased salinity levels can clearly improve the tolerance of shrimp to ammonia.

Nonetheless, because nobody will usually experiment with salinity in freshwater tanks or even saltwater tanks, I do not see any reason to dig deeper on this matter.

8. How to Treat and Prevent Ammonia Poisoning in Shrimp Tanks

First of all, you need to find the cause of ammonia and fix it. For example: 

8.1. Overfeeding

Overfeeding is the simplest way to get ammonia in your shrimp tank.

Food items that remain uneaten for long periods will rot — thereby increasing the ammonia level in the water column. The feed must be limited to the amount that is consumed within a few hours.

Therefore, avoid overfeeding at all costs. Remember, it is better to underfeed than overfeed. Use feeding dishes for better control.

You can also read my article “How Often and How Much to Feed Shrimp“.

8.2. Overdosing medications

Check recommendations and follow instructions. Double-check your calculations of water volume (take into consideration decorations, driftwood, stone, substrate, etc.).

If you are still worried about using medications in your tank due to fear of the shrimp dying, you can begin at a ½ dose at first.

Important: Some medications can harm beneficial bacteria. In this case, do not forget to turn the filter off or even remove filter media so that beneficial bacteria will not be affected. Do your research regarding your situation.

8.3. Biological filtration capacity

It is all about the beneficial bacteria. An inadequate number of these bacteria will definitely lead to the accumulation of ammonia in the aquarium water. 

Therefore, be very careful with:

  • putting shrimp in a new or an uncycled tanks;
  • changing substrates (or make lots of big changes in the tank) without preparation. Remember, beneficial bacteria attaches itself to any surfaces throughout the aquarium, it is on the décor, live or fake plants, driftwood, rocks, tubes, heaters, glass, substrate, and, of course, in the filter of your tank;
  • over cleaning your filtration. Do not replace your filter (cartridges) without preparing a new filter media. You can also read “How to Clean an Aquarium Filter”.

Note: Personally, I do not think that overstocking is a big problem in shrimp keeping. Unlike fishes, dwarf shrimp produce very little bioload. Nonetheless, if your tank is new, I’d keep it in mind anyway.

8.4. Cleaning

Leftovers and decaying plants should not be in the shrimp tank. Do not forget to do your maintenance.

8.5. Using plants

Most plants use ammonium to live and grow. Even if there are nitrates they often need to convert nitrates back into ammonium. So, using plants (especially floating plants) is perhaps the most cost-efficient and environmentally friendly way to provide extra filtration for your tanks.

Note: Just keep in mind that their efficiency at removing ammonia depends on how fast they grow. If something is not growing fast, it does not need a lot of food.

9. Ammonia and Emergency in Shrimp Tank

What should we do in cases of emergency situations? In shrimp, ammonia poisoning acts pretty fast, therefore, we need fast countermeasures.

1. Option # 1: Evacuate shrimp

Move them to the quarantine tank if it is possible.

2. Option # 2: An immediate water change

Depending on the ammonia level, perform large water changes, up to 50% at first, followed by subsequent water changes of about 10% every day to drive the ammonia level down significantly.

By changing 50 %, we will reduce ammonia concentration by 2 times. So, why don’t we do 75% water changes or even more?

Because even 50 % water change is already too stressful and dangerous to the shrimp. Big water changes can cause molting problems (like the White ring of death). Nonetheless, big water change is a lesser evil than exposure to ammonia.

Once your shrimp are moved to the quarantine tank or after a water change, we can do the following steps.

3. Use pollutant binder

Use a good water conditioner or pollutant binder. For example, a standard dose of Seachem Prime (link to check the price on Amazon) neutralizes 1 ppm of ammonia for 24-48 hours. During this period it binds ammonia and converts it into a safe, non-toxic form that is readily removed by the tank’s biofilter.

Remember: this is a temporary solution! In 24-48 hours ammonia will become toxic again. Of course, you can re-dose every 48 hours as necessary but be careful with overdosing. 

4. Cleaning and vacuum the substrate

Vacuum the substrate to get rid of detritus that contribute to the ammonia problem. Siphoning will decrease the concentration of ammonia and prevents further ammonia build-up from microbial decomposition.

5. Check for any rotting organic

Remove any dead plants or decaying organic. Just like shrimp waste, rotting plants will also produce ammonia.

6. Add Nitrifying Bacteria or Used Filter Media

How To Setup an Easy Quarantine Tank beneficial bacteriaHaving raised ammonia levels in your shrimp tank may be the result of problems with the nitrogen cycle. For example, it can be a lack of nitrifying bacteria to break down ammonia to nitrites.

At this juncture, it would be reasonable to add a bacteria starter like Tetra SafeStart Plus (link to Amazon to check the price) or filter media from a disease-free cycled tank.

Simply obtain bacteria starter culture from your pet store or local fish store and add it to your aquarium.

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10. Testing Ammonia

In an established shrimp tank, an ammonia test should be done and recorded once per week. 

In case of the slightest suspicion of ammonia poisoning, you should immediately test for ammonia. Any detectable amount of ammonia should be addressed immediately! Hopefully, we catch it before it affects our pets.

Important: Almost all known ammonia test kits measure something called total ammonia nitrogen (TAN). It is all of the ammonia forms in the tank  (ionized (NH4+) and un-ionized (NH3)). Because of that, we do not get the correct reading. These tests just give us a general understanding.

Luckily we can use a free ammonia calculator for that. This calculator will give you detailed information based on your pH and temperature.

In any case, I need to stress it out – test kits should be reading zero ammonia! The fact that some form of ammonia is less dangerous, does not mean that it is OK to have it! No, it means that something is off in your tank, and need to fix it!

In Conclusion

Ammonia can easily accumulate to an unsafe level and become a serious problem in shrimp tanks. Ideally, a fully cycled tank should not have any traces of ammonia.

The toxic effects of ammonia are well documented in shrimp.

Ammonia stress is an important factor that impacts shrimp’s respiration, metabolism, immunity, osmotic regulation, excretion, molting, growth, reproductive capacity, and disease tolerance. It is also known to be lethal to these crustaceans.

It is absolutely crucial to test your tank water regularly to ensure that ammonia levels do not start building up.

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Does ammonia affect shrimp?

Yes, shrimp are very sensitive to ammonia. Ammonia affects shrimp’s immunity system and makes them susceptible to other pathogens. It will damage their digestive tract causing reduced feeding rates, stunted growth, and other metabolism changes.

How much ammonia can shrimp handle?

The only safe level of ammonia is 0 parts per million (ppm). Shrimp can tolerate low levels of ammonia (up to 0.05 mg/1 (ppm)), however, prolonged exposure can still be harmful to shrimp.

Can shrimps survive ammonia?

Not for long. Ammonia is very harmful to shrimp and it needs to be addressed in your tank immediately.

Will Shrimp keep a tank cycled?

Yes, even though shrimp do not produce a lot of waste, it should be enough for the beneficial bacteria to keep the tank cycled.

How do I get rid of high ammonia in my shrimp tank?

You need to do up to 50% water change immediately. Vacuum your gravel. Remove any rotting plants. Check your filtration. Control feeding.

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