No matter if you are using a freshwater aquarium or a saltwater aquarium, the high concentration of nitrates in the fish tank can prove to be quite a huge menace. We will try finding out what high nitrate levels can do to your beloved fish and how to lower nitrate levels in a fish tank more efficiently and effectively.
The best way to reduce nitrate levels in a fish tank is to perform regular and frequent water changes. Make sure to remove the debris and other fish waste in the gravel. If you are using tap water in the aquarium, make sure that the tap water does not contain nitrates. It is also advisable to change the filter pads at least once or twice a week. Also, avoid turning off filter at night. These tips hold good in how to lower nitrates in a freshwater aquarium or a saltwater aquarium. Partial water changes are the best option to improve the level of nitrates.
What is Nitrate in Aquarium?
Nitrates are the harmful chemical compounds in the aquarium tank which result from the biological composition in the tank. The major source of the nitrates in the fish tank includes faeces, urine and excess food. Nitrates are generally formed when the bacteria inside the aquarium water convert the ammonia into nitrite and then into nitrate.
Under normal circumstances, the nitrate levels in the natural waters tend to be extremely low. This is so because of the larger quantity of water and the hydrologic cycle. The nitrates are formed as part of the nitrogen cycle. The Nitrosomonas bacteria converts the ammonia into nitrite nd this nitrite is subsequently converted into nitrate.
If you are a newbie aquarist, you may get confused between nitrite and nitrate. It may be noticed that nitrites can be very toxic for the fish. Nitrate too is toxic, but to a lesser extent. Moreover, it is much easy to remove nitrate from the fish tank.
The Nitrogen Cycle – The Important Ecosystem of Aquarium Life
The Nitrogen cycle in the context of an aquarium refers to a natural process where uneaten food and fish waste are converted into harmless or less toxic elements that would ultimately benefit the ecosystem inside the aquarium. The cycle typically involves converting ammonia into nitrite and then into nitrate. This process is facilitated by the beneficial bacteria present in the aquarium.
Here is a complete breakdown of the Nitrogen cycle –
-
Ammonia Formation:
Fish and decaying organic matter produce ammonia (NH3), which is toxic to fish.
-
Nitrite Conversion:
Beneficial bacteria, like Nitrosomonas, convert ammonia into nitrite (NO2). Nitrite is also toxic to fish.
-
Nitrate Conversion:
Another type of beneficial bacteria, Nitrobacter, converts nitrite into nitrate (NO3). Nitrates are generally less toxic to fish at low to moderate levels.
-
Nitrate Removal:Plants, algae, or water changes can help remove nitrates, balancing the cycle.
The Dangers of High Nitrate Levels for Fish and Plants
The aquarium Nitrate levels are not normally as dangerous as the nitrite levels. Most of the fish can tolerate a nitrate level of up to 550 ppm. However, continuous exposure of nitrates, even tolower levels, can be damaging. It can affect the cell development of your fish severely. It can cause lethargic behaviour, faded colors, a poor immune system and similar other issues.
Under ideal conditions, experts claim that a nitrate concentration should never be more than 20 ppm. An ideal long-term concentration should be around 10 ppm. One of he huge concerns that a high level of nitrate concentration is that it can cause the algae to bloom beyond control.
What are the Optimum Nitrate Levels in an Aquarium?
The ideal nitrate level in your aquarium can depend on several factors, most notably whether you have live plants. In a heavily planted aquarium, nitrates actually serve as an essential nutrient for plant growth, and a level around 50 ppm is often considered beneficial.
However, in fish-only tanks or tanks with minimal plant life, lower nitrate levels are generally preferred to prevent stress on the fish and discourage algae growth. Aiming for nitrate levels below 20 ppm in these types of setups is a good guideline.
How to Monitor Nitrate Levels in Your Fish Tank?
The best way to monitor the nitrate levels in a fish tank is to measure the nitrate in tank water using a test kit. You can simply follow the instructions available on the kit and measure the levels and maintain it within the permissible levels. The test kit generally uses a colour chart with which you can compare the colour produced by your test.
The video here should give you an idea into how to measure nitrate level in a fish tank –
How To Lower Nitrates In Fish Tank – 7 Best ways to Lower Nitrates in Aquarium
Now that we know the highest nitrate levels permissible in a fish tank, we will move to find how to lower nitrates in an aquarium through a few easy steps.
The easiest options for lowering nitrates in a fish tank can include adding more live plants, removing and cleaning filter media, avoiding overcrowding, and not feeding more than needed. Overfeeding leaves more uneaten food or causes more fish waste, which causes more ammonia production. This subsequently leads to the concentration of nitrates.
It is not possible to remove all the nitrate from the fish tank, but making sure to keep nitrate levels under control can help. You can consider the following methods to lower nitrates in the aquarium. It is advisable to keep a level of 10 ppm or lower so that your fish can have a stress-free life.
1. Change the aquarium water frequently
Frequent and regular water changes will ensure that the level of nitrates does not increase in your fish tank. Each time you changee water, ensure that you have treated it for chlorine. Using tap water that has nitrate levels higher than 40 ppm is not advisable.
Also check out this if you are a bird lover – Do Birds Make Great Pets? Unraveling the Pros and Cons of Avian Companionship
2. Introduce live plants
The high nitrate syndrome is also called old tank syndrome. Introducing live plants into your tank should be one of the best means to lower nitrates in your aquarium. Plants need nitrates for nutrition. If you have a saltwater aquarium and face high nitrate levels, use live plants in your tank. Live plants can also be a good option to help control algae growth. Aquarium plants are natural filters as they need nitrates for their growth. The use of nitrate-reducing aquatic plants is highly recommended. Studies have shown that fast-growing aquatic plants like water sprite (Ceratopteris thalictroides) can significantly reduce nitrate levels in aquarium water.
While water changes are the best way to lower nitrates in the aquarium, you can also use the nitrate-removing filter media for an effective reduction of nitrates. A bio-media that uses bacteria for filtering the water and removing nitrates can be a good alternative to water changes. Pay attention to the type of bacteria being used. Anaerobic bacteria is more effective in removing the nitrates.
3. Use nitrate-reducing media
Nitrate removal media can be yet another way you can use to reduce the high nitrate levels is by using nitrate-reducing media. One good example here can be to use high-performance filter media. It can effectively help you lower nitrates in your aquarium.
Beyond standard mechanical and biological filter media, there are specialized media designed specifically for nitrate removal. Some of these media work by providing an ideal environment for anaerobic bacteria to colonize and perform denitrification. Others may chemically bind to nitrates, removing them from the water. Researching the different types of nitrate-removing media available can offer another effective tool in your arsenal against high nitrate levels.
4. Use specific equipment to reduce Nitrate levels
You can make use of the special techniques for reducing the nitrate level in a fish tank. A few good options can include introducing the techniques such as Reverse Osmosis, Ion Exchange and Water Distillation methods. The best option would be to use the treated water in your tank.
There are Reverse Osmosis units specifically designed for aquariums. You can check out any of them. However, the Reverse osmosis process can be counterproductive as it tends to remove the essential nutrients from the water. You can also use the water distillation option, wherein water is heated to produce steam. This steam is then collected and cooled to form water.
5. Algae Turf Scrubber (ATS)
This method is best suited for freshwater aquariums, but can also be used for saltwater aquariums. This will help you reduce nitrates through the process labelled as biological filtration. This method involves the use of a device that uses light and mineral-rich water, which subsequently adds up bacteria to the tank.
This will eventually make the bacteria absorb the nitrates. That way, you do not use any chemicals, but depend on a purely biological way of filtering the water and removing nitrates from the tank.
Pro Tip: Do not use this method if you have live plants in your aquarium. It can kill your plants.
6. Use Refugium Sumps
The method is the right one to reduce nitrates if you are using a saltwater aquarium. This is yet another biological filtration method that effectively reduces the nitrate level in your tank.
For a more proactive and natural approach to managing nitrates, consider setting up a refugium. A refugium is essentially a separate, smaller tank connected to your main aquarium, often housed in the sump. The primary purpose of a refugium for nitrate reduction is to cultivate fast-growing macroalgae, such as Chaetomorpha (often called ‘Chaeto’), which readily absorb nitrates from the water as they grow. Regularly harvesting a portion of this algae effectively removes the nitrates from your overall aquarium system. Refugiums also offer other benefits, such as providing a safe haven for beneficial microfauna that can contribute to a healthier aquarium environment
7. Deep Sand bed method
Another natural method for long-term nitrate reduction involves the creation of a deep sand bed (DSB) in your aquarium or sump. This typically involves a layer of fine sand at least four inches deep. In the lower, oxygen-depleted layers of the sand bed, anaerobic bacteria can thrive.
These bacteria perform denitrification, converting nitrates into nitrogen gas that escapes the aquarium water. While effective, establishing and maintaining a healthy DSB requires careful planning and consideration of factors like sand grain size and potential for disturbance.
The nitrate levels from 0 to 40 ppm are generally safer for the aquarium fish. If the nitrate levels go above 80 ppm, that can become a little toxic for your fish. However, nitrites, even in small quantities, can be very toxic. Even Nitrite levels of above 0.75 ppm in water can cause the fish to get stressed out, and any level above 5 ppm can kill your fish.
However, even when the nitrate levels of 40 ppm can be treated safer, it can get toxic over time; it is advisable to keep a nitrate level of not more than 5 to 10 ppm of nitrate in most of cases.
A Special Care Guide for the Initial Setting Up
We talked about the New Tank Syndrome above. This refers to the abnormal concentrations of ammonia or other harmful chemicals observed when you set up an aquarium for the first time, or a new aquarium.
During the initial cycling of a new aquarium, as beneficial bacteria colonies are establishing, you will likely see fluctuations in ammonia, nitrite, and eventually nitrate levels. It’s common for nitrate levels to rise significantly during this phase. If nitrate levels become very high (over 80-100 ppm), it’s essential to perform partial water changes to keep the levels within a safer range for any livestock you may have introduced.
However, fish-in cycling is generally discouraged. Regular testing of your water parameters will guide you on when and how much water to change. Once the cycle is complete (ammonia and nitrite consistently at zero), you can then focus on maintaining stable nitrate levels through regular maintenance.
Is There Any Chemical to Reduce Nitrates in an Aquarium?
Yes, there are several chemicals that can help reduce nitrates in an aquarium. Algone is one of the most common options to help reduce the nitrates in an aquarium.
Some of the chemicals to reduce nitrates in the aquarium would include
- Seachem Purigen – This is a fast-acting nitrate remover that works with resin to remove the organic compounds.
- ALGONE – It can gently remove nitrates. It is also helpful in preventing the issues associated with nitrates and similar compounds
- EA Premium Pad – This is a good, affordable nitrate remover you can use
- Water Wisteria – This can be a powerful nitrate-reducing plant.
Why does Nitrate Level rise – The Common Causes
A few of the contributing factors that may increase the level of nitrates in the aquarium include decaying plant material, leftover fish food, Detritus, overfeeding, dirty filters, and overstocking. Tap water, too, can be a reason for an increased level of nitrates in the aquarium water.
Overfeeding and overstocking have been found to be the primary cause of high nitrate levels in the aquarium. Avoid overcrowding your fish tank. If you love keeping more fish, go for a bigger tank instead. Overcrowding can at times result in nitrate spike in your aquarium.
The Parting Thoughts
High levels of nitrates in the fish tank can be a worrying factor. It can make your beloved fish get suffocated and even die. Maintaining an optimum level of nitratees in the aquarium is essential, and the tips outlined above should help you make the right decisions in this context.
Check out the different ways to lowerthe tank’s nitrate levels and opt for the best ways to lower nitrates in your tank.
FAQs
What happens if nitrate levels are too high in a fish tank?
Higher levels of nitrates in the fish tank can cause significant algal growth. This is also called an algal bloom. It can have a negative impact on the health and well-being of your tankmates.
What causes the high nitrate in a fish tank?
Some of the primary reasons that can cause a high nitrate level in the fish tank include detritus, decaying plant material, dirty filters, over-feeding, and overstocking the aquarium. In addition, the tap water that you add to the tank as part of a water change would also cause the nitrate levels to rise if your tap water has a higher concentration of nitrates.
Are nitrates bad for fish?
Nitrates, in themselves, are not toxic to fish, especially in freshwater aquariums. However, the higher levels of nitrates can result in the fish suffocate or even dying. Nitrate is much less harmful when compared to nitrites. However, you can reduce the high nitrate levels through frequent water changes and introducing live plants inside the aquarium.
[…] The Ultimate Guide on How to Lower Nitrates in your Aquarium […]