How To Lower Nitrates In Fish Tank?

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How To Lower Nitrates In A Fish Tank The Unrivaled Guide

Have you ever observed the growth of algae inside your aquarium? It happens because of the excess quantity of nitrate in the water tank.

When you ignore the maintenance of the tank, it results in an increase in nitrate. Nitrate is the main component of fertilizer. The algae take this from the surroundings.

The most challenging part of the maintenance of the aquarium is the control of algae growth, which is the consequence of nitrate/nitrogen.

It is produced due to the nitrogen cycle inside the aquariums and the nitrogen-consuming algae growth. Inadequate maintenance results in an increased nitrogen quantity.

Plants require nitrogen in order to grow. Either the nitrate is absorbed by the plants, proper maintenance of aquarium water or chemical filters can help you get rid of this.

Nitrate and nitrite are two different chemicals, but they sound familiar. Nitrite is a very explosive material for fish, even in small quantities, while nitrate is less poisonous for fish but still harmful. Read on to learn more about how to get rid of this nitrate from the aquarium.

What Are Nitrates?

Nitrate is the most influential component waste of in aquariums. It is produced from ammonia. The main causes of its production are the decay of plant matter, decomposing leftover food, and fish feces. The bacteria inside the aquarium first convert the ammonia into nitrite, then into nitrate.

Image of an amazing aquarium

Nitrite is a very dangerous chemical and can easily kill thousands of aquarium animals in small quantities. Meanwhile, the nitrate is less toxic in contrast to the nitrite. It would require 100 times more nitrate in order to execute the same destruction.

The increase in nitrate in the aquarium is due to the decreasing level of pH. If you introduce a new fish during this period, it can cause shock and eventually death.

How Do You Test For Nitrates?

The nitrate color scale gives an estimate of the nitrate concentration between 0.0 and 160.0 ppm.

Here is how to conduct a nitrate test:

  • Put 5 mL of aquarium water into a vial.
  • Shake the nitrate testing bottle well before use for one to five seconds.
  • Squeeze ten drops from the nitrate testing bottle #1 into the vial, keeping it upside down.
  • After sealing the vial, shake ferociously for five seconds.
  • Shake bottle #2 of the nitrate test vigorously for 30 seconds.
  • Squeeze ten drops from the nitrate testing bottle #2 into the vial, keeping it upside down.
  • Shake ferociously for 60 seconds with the vial cap on.
  • Then, compare the measurement to the color scale after waiting five minutes.
  • A colorless sample represents the absence of nitrates. Any hints of pink in the sample show that nitrate is present in the aquarium.

Safe Nitrate Levels In The Aquarium

The natural level of nitrate in the water is very low. It is usually less than 5 ppm (parts per million). The preferable amount of nitrate in the freshwater aquarium is below 25 ppm, although it should be kept less than 50 ppm at any cost.

If algae is growing in your aquarium and you are trying to weed it out, then you should keep the nitrate level in the water below 10 ppm.

The high level of nitrate has an adverse impact on the lives of fish. The same situation arises another problem which is the decrease in oxygen level, resulting in additional stress on the fishes

Nitrate Poisoning vs Nitrate Shock

The two terms are well defined on the basis of the intensity of nitrate in the aquarium water. In contrast to nitrate shock, which is an acute condition with a sudden onset, nitrate poisoning is a long-term issue.

The leading cause of nitrate poisoning is the increase in the level of nitrates in the aquarium. It happens when you regularly ignore the maintenance of the aquarium. There are many other causes of increased nitrate levels, which include overfeeding and overstocking.

Nitrate shock arises when you put your new fish in aquarium water that is highly dense with nitrates. Highly dense refers to the quantity of nitrate up to several hundred mg per liter.

It happens due to the sudden rise in the level of nitrates. On the other hand, if you decrease the nitrate all of a sudden, the fish will feel the same shock.

The Potential Dangers of Excess Nitrate Levels

You might have been told a lot of times that nitrates are not that harmful to fish. Also, the fish are able to overcome the effects of a nitrate rise.

The reality is actually opposed to it. The high level of nitrate has negative effects on fish cell development as well as on invertebrates.

Image of goldfishes in an aquarium

At over 30 ppm nitrate, your fish might start showing critical signs of it, like a poor immune system, poor color, lethargy, etc.

Many professional aquarists claim that you should maintain the aquarium nitrate level below 20 ppm. At the same time, if you want to give them a unique environment to grow in, the level should be kept below 10 ppm.

Still, the small amount of nitrate in the aquarium water can cause a lot of algae blooms. This may also result in planktonic water (green water).

How To Lower Nitrates In Aquariums?

The easiest way to lower the nitrates in the aquarium water is by changing the water. If your tap water has less nitrate quantity, you can replace it on a regular basis, which will lower the nitrates in the aquarium. A few of the other leading ways are:

#1- Installing A Refugium

Refugiums can assist in lowering the nitrates in the water. These are valuable as they help in exporting waste and other harmful elements outside the tank. Refugium helps in providing a comfortable and safe haven for these small creatures to grow and reproduce.

Image of two fish tanks with vegetation

The bugs that accommodate the refugium also devour the leftover food and detritus. If any of the bugs from your tank make their way into the refugium, they will help feed the animals in your tank and increase the biodiversity in the aquarium.

#2- Using Microbes

One can also control the level of nitrogen inside the water tank by introducing microbes inside it. These microbes either use it as an organic compound or transform it into other substances. The microbes are easily available on the market.

There are two main types of microbes, mainly aerobic and anaerobic. When compared to anaerobic ones, aerobic ones are quicker and can quickly swallow these nitrates.

Aerobic microbes also require some carbon feeding, such as ethanol. On the flip side, anaerobic bacteria are slow, but they do not need carbon.

#3- Reduced Feedings

In order to get rid of nitrates in the aquarium, one should control the feeding of the fish. Never feed too much to the fish in the aquarium as the remaining food will settle down at the bottom of the tank and decay. The decay and rotting food will result in a rise in nitrates.

Image of fish eating fish flakes

Measure the quantity of food your fish consume and give them accordingly. This will save you money as well as maintenance. Make portions for their daily food. It will help you feed your fish.

#4- Water Changes

The regular maintenance of water changes can result in the reduction of nitrate levels. It is easy if you are carrying out water change to a large extent.

The water changes can lower the nitrate level in one shot. It completely depends on you. How much nitrate do you want to level down? 30% just change the thirty percent water and see the results.

#5- Don’t Overfeed Your Fish!

The amount of nitrate fish produced is directly proportional to the quantity you feed to them. If you feed them more than required, it will result in a rise in the nitrate level in the aquarium water. At the same time, highly accommodated fish tanks will produce more nitrates.

Image of different fish in aquarium

It is obvious that too many fish in a tank and overfeeding them can cause chronic problems for them. So always keep in mind that you keep fewer and smaller fish and don’t overfeed them. Otherwise, the consequences will be a rise in the nitrogen level.

#6- Clean Your Filter

You can also make use of the special filters, referred to as denitrators. These special devices help in reducing the amount of nitrate in the aquarium water. These devices are very expensive if you compare them with any other filtration units.

You can also purchase nitrate-lowering media from your local fish store and utilize them in the filters you have. It will cost you less than the costly denitrators. These will result in a reduction in the nitrate level, but they need to be changed with the passage of time.

Final Verdict:

In a nutshell, by following the aforementioned tricks, you can easily get rid of the increased nitrate level in aquariums.

Nitrogen can even kill your fish within a short time or give them a shock. So, never ignore the maintenance of your aquarium, as it will affect the fish it accommodates.

The nitrate quantity will increase and will impact them in the worst way. Maintain the nitrate quantity up to or below 10 parts per million, as stated by many professionals. The maintained nitrogen aquarium will give the fish suitable conditions to grow and prosper.

Stick yourself with the above-described procedure. If you implement the above tricks in the best way, the outcomes will be in your favor.

Frequently Asked Questions

#1 – What is the fastest way to lower nitrates in an aquarium?

Altering the water in your setup is the quickest and simplest way to reduce nitrates. Your nitrate level will decrease if you replace the tank water with tap water, as long as the tap water has less nitrate in it than the tank water does. To confirm this, check the nitrate levels in both your freshwater tank and your tap.

#2 – How do I lower nitrates in my fish tank naturally?

The aquarium’s overall nitrate level can be reduced by performing routine water changes with water that contains little to no nitrate.

Using reverse osmosis (RO) or deionized water (DI) can help keep nitrate levels low when performing a water change if the tap or well water in your area has a high nitrate content.

#3 – How long does it take for nitrates to go down in a fish tank?

It basically depends on the type of plants you put inside. It also depends upon the bioload of the tank. If you have a light stock and you have planted fast-growing plants, they can bring it down within a few days. If it is not light stocking, it may take a week.

#4 – How long can fish live with high nitrates?

The fish can live up to a few days or a few weeks. When fish are exposed to high nitrate levels, they eventually die within 24 hours. Many owners are not aware of the problem until the fish are dead or near death.

#5 – Will nitrates go down on their own?

There are many ways to reduce the level of nitrate in the aquarium. You can make use of the microbes (aerobic and anaerobic), water changes, and you can even change the filter in it. But when you talk about a complete and healthy system, then yes. The level of nitrates goes down on its own.

#6 – Does the water conditioner remove nitrates?

Some water conditioners remove nitrates. They usually convert the nitrates to nitrogen gas, allowing them to escape from the surface of the aquarium.

You can also say that the conditioner restrains the nitrates, rendering them harmless to fish. They make it possible for the bacteria in your biological filter to destroy them.

#7 – Is 40 ppm nitrate too high?

In order to provide the best living environment for your fish, it is important that the nitrate level be kept between zero and forty ppm. If it goes over 80 ppm, fish may suffer harm.

#8 – Do aquarium plants remove nitrate?

By including plants in your aquarium, you can control your nitrate levels in one of the simplest and most natural ways possible.

Because plants that draw nutrients from the water column also draw nitrates for nutrition, your plants will grow more quickly, and your nitrate levels will be lower.

#9 – What level of nitrates is toxic to fish?

In water, nitrite concentrations above 0.75 ppm can stress fish, and concentrations above 5 ppm can be toxic. Fish are generally safe in nitrate concentrations between 0 and 40 ppm. Anything over 80 can potentially be toxic.

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