Do Neon Tetras Need A Filter? (Why It’s Important)

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Arranging a neon tetra tank raises many questions, including what equipment these delicate creatures actually need.

One question I often receive is whether they require a filter. In this article, I will answer this question, and walk you through the entire process of picking the right one for your tank.

Let’s dive in.

Do Neon Tetras Need A Filter?

When it comes to neon tetra care, filters are crucial, mainly because:

  • Waste Management: A filter helps remove physical waste and uneaten food from the water. Without a filter, these materials would decompose and negatively impact the water quality.
  • Biological Filtration: The filter also provides a home for beneficial bacteria that convert harmful substances like ammonia (produced by fish waste and decomposing food) into less harmful substances like nitrites, and then into even less harmful substances like nitrates.
  • Chemical Filtration: Some filters can also help remove harmful chemicals from the water, such as heavy metals or chlorine, depending on the specific type of filter media used.
  • Oxygenation: As the filter pushes water around, it helps oxygenate the water by increasing the surface movement which facilitates gas exchange. This is especially crucial for neon tetras who need a well-oxygenated environment to thrive.
  • Prevents Disease: By keeping the water clean, a filter can help prevent the spread of diseases among your neon tetras. This is especially crucial when dealing with wound neon tetras, as they are already vulnerable and poor water conditions can exacerbate their health issues.
  • Stabilization of Parameters: Filters help in maintaining stable water parameters (like pH, temperature, hardness, etc.). This consistency is critical for the health of neon tetras who prefer certain water conditions.

Considering these factors, I would highly advise you to choose a filter for your neon tetra tank.

Also Read: Neon Tetra Tank Setup

What Are The Advantages Of Using A Filter In Your Neon Tetra Tank?

Installing a filter in your neon tetra tank offers numerous benefits, making it a worthwhile investment. Here are some of the primary advantages you’ll experience:

1. Promotes Water Movement

  • A filter can help to create a steady flow of water in the tank, mimicking the natural current found in a river or stream.
  • This flow of water helps to evenly distribute heat and oxygen throughout the tank, promoting the overall health and activity level of the neon tetras.
  • Continuous water movement prevents stagnation, which can otherwise lead to the growth of harmful bacteria or algae.

Also Read: Do Neon Tetras Need A Bubbler?

2. Reduced Frequency Of Water Changes

  • A good filter reduces the frequency of water changes, saving you time and making fish care easier.
  • This can help to minimize the stress experienced by the fish during water changes, which can otherwise lead to health issues.
  • By mechanically filtering out debris and chemically removing toxins, the water quality is maintained for longer periods.

3. Elimination Of Ammonia, Nitrites, And Nitrates

  • Filters can host beneficial bacteria that take part in the nitrogen cycle, transforming harmful substances like ammonia and nitrites into less harmful nitrates.
  • Ammonia and nitrites are highly toxic to fish and can cause a range of health problems, including gill damage and even death. Filters can help to ensure that levels of these substances are kept low.
  • While nitrates are less harmful than ammonia or nitrites, high levels can still be detrimental to fish health. Regular use of a filter (along with periodic water changes) helps to maintain safe levels of nitrates.
  • Some types of filters can also remove nitrates entirely, providing an even healthier environment for your neon tetras.

What Type Of Filter Is Best For Neon Tetras?

Unfortunately, there is no one-size-fits-all filter for neon tetra tanks.

However, canister filters are highly recommended for larger tanks, while power filters are more suitable for smaller tanks.

Here’s a brief overview of the various filter options available:

1. Canister Filters

  • Canister filters are powerful and versatile, making them suitable for larger aquariums that house a lot of fish, including neon tetras.
  • They are highly efficient in biological, chemical, and mechanical filtration, as they have larger chambers for holding various media types.
  • They are usually placed outside the tank, which can save space inside the tank for the fish and decorations.
  • These filters push water instead of pulling it, creating an effective water flow. However, the flow rate should be adjusted so that the neon tetras, which prefer calm waters, are not stressed.
  • While they can be more expensive than other types, their performance and versatility make them a pretty good investment.

2. Power Filters

  • Hang-on-back filters, frequently referred to as power filters, are among the most prevalent types of filters employed in residential aquariums.
  • They provide excellent mechanical, chemical, and biological filtration. They are pretty easy to install and don’t require much maintenance.
  • They hang on the back of the aquarium, hence saving space inside the tank. The intake tube extends into the tank and sucks water up into the filter.
  • The adjustable flow rate makes it easy to create the ideal conditions for your neon tetras.
  • Generally, power filters are a cost-effective and efficient choice for small to medium-sized tanks.

3. Internal Filters

  • As the name implies, internal filters are placed inside the aquarium. They are ideal for small to medium-sized tanks, including those housing neon tetras.
  • These filters provide good mechanical and biological filtration, and some models offer chemical filtration as well.
  • They are usually cheap and easy to install and maintain. However, they do take up space inside the tank, which could be used for decorations or plants.
  • They create a gentle flow of water, which makes them suitable for neon tetras that do not appreciate strong currents.

4. Undergravel Filters

  • They are positioned underneath the aquarium’s substrate, performing dual roles in mechanical and biological filtration.
  • These filters remain hidden from view, preserving the aesthetic appeal of the aquarium while not consuming interior tank space.
  • They generate a gentle current suitable for species like neon tetras that prefer less turbulent waters.
  • The capacity for chemical filtration with these filters is often not as strong as other types.
  • Maintenance can be somewhat challenging due to the potential accumulation of waste or uneaten food within the gravel.
  • While they may not be the first choice for the highest level of filtration, they can serve effectively in smaller tanks that are consistently well-kept.

Factors To Consider When Buying A Filter For Your Neon Tetras

When you decide to purchase a filtration system for your neon tetras, there are certain factors that are crucial to consider:

  • Tank Size: The size of your tank plays a crucial role in determining the type of filter you should buy. Some filters are designed for smaller tanks, while others are better suited for larger aquariums.
  • Filtration Type: Different filters offer different types of filtration – mechanical, chemical, and biological. Ideally, you want a filter that offers all three.
  • Flow Rate: Neon tetras are native to slow-moving waters, so a filter that creates strong currents might not be the best choice. Look for a filter with an adjustable flow rate to ensure your tetras are comfortable.
  • Maintenance: Some filters require more maintenance than others. Reflect on the amount of time and energy you’re prepared to invest in the upkeep of your filter.
  • Noise Level: Some filters can be quite noisy, which may be disruptive for you and stressful for the fish. Consider choosing a filter that operates quietly.
  • Space: Consider the space you have available. Some filters, like internal and undergravel filters, will take up space inside the tank, while others, like canister and power filters, hang on the outside.
  • Price: Lastly, consider your budget. Some types of filters can be quite expensive, so find a balance between cost and quality that works for you.

When it comes to neon tetras, my pick would be the Fluval C4 Power Filter (link to Amazon).

Alternative Steps In The Absence Of A Filtration System

In situations where your filter malfunctions or hasn’t been purchased yet, there are temporary measures you can take to maintain water cleanliness.

However, keep in mind that these are short-term solutions, and in the long run, investing in a filter is advisable.

1. Avoid Overcrowding Your Aquarium

  • Overcrowding can lead to rapid waste buildup, increasing the levels of harmful substances in the water.
  • A less populated tank results in a more stable environment with fewer fluctuations in water quality.
  • A less crowded tank can also reduce stress among fish, leading to healthier and happier pets.

2. Increase The Frequency Of Water Changes

  • Regular water changes help remove waste materials physically from the tank.
  • Water changes also dilute harmful chemicals that may have accumulated over time.
  • While this approach may demand a bit more effort and time, it’s a vital step in preserving the quality of water when a filter isn’t in use.

For smaller aquariums, water changes should be more substantial and frequent. Use an API Master Test Kit (link to Amazon) to monitor the water daily and adjust as necessary.

3. Utilize Ammonia Neutralizers

  • Ammonia neutralizers chemically neutralize ammonia, which is harmful to fish.
  • The use of these products can help maintain safe water conditions for your neon tetras without a filter.
  • Keep in mind, neutralizers should be used according to their instructions to avoid overuse.

My recommendation in this category is the well-known API Ammo Lock (link to Amazon).

4. Incorporate An Abundance Of Plants

  • Plants can be seen as a natural filtration system as they eliminate toxins like ammonia, nitrites, and nitrates.
  • Through the process of photosynthesis, they not only beautify your aquarium but also oxygenate the water, promoting a healthier environment.
  • Besides their cleansing and oxygenating properties, plants enrich the habitat by providing food and shelter for various fish species, enhancing the overall ecosystem within your tank.

Also Read: 11 Plants Your Neon Tetras Will Love In Their Tank


To recap the key highlights I mentioned earlier:

  • Filters are crucial for neon tetras, especially in smaller aquariums, as they help maintain water quality and minimize the risk of illness.
  • Having a filter in your neon tetra tank offers advantages such as promoting water movement, reducing the frequency of water changes, and eliminating harmful chemicals.
  • Canister filters are recommended for larger tanks, while power filters are suitable for smaller aquariums. Internal filters and undergravel filters are also options to consider.
  • In the absence of a filter, it is crucial to avoid overcrowding the aquarium, increase the frequency of water changes, utilize ammonia neutralizers, and incorporate live plants to maintain water cleanliness.