10 Aquarium Fish Species that Can Live Without a Filter
Discover which fish species can live in aquariums without a filter. I’ve compiled a list of 10 beginner-friendly and hardy fish that can be kept without an artificial filter system.
Betta Fish (Siamese Fighting Fish)
The Betta Fish, also known as Siamese Fighting Fish, is an incredibly popular and beautiful species suited for small aquariums. With their stunning colors and distinctive flowing fins, they’re sure to make a statement in your tank.
- Tank Size: 2.5-5 gallons (9-19 liters)
- Care Level: Easy
- Adult Size: Up to 3 inches (7.6 cm)
- Temperature: 75-82°F (24-28°C)
- Diet & Feeding: Carnivorous, requires a diet of high-quality pellets, frozen, and live foods
- Lifespan: 2-4 years
- Behavior: Aggressive with other Bettas, but generally adapts well with other peaceful tankmates
Keep in mind that while Betta Fish can survive without a filter, a gentle sponge filter is recommended to maintain water quality. Regular water changes will also be crucial for keeping your Betta Fish healthy and happy in a no-filter tank.
Guppies
Guppies are a favorite among beginners and experts alike, thanks to their hardy nature, low maintenance, and eye-catching colors. They are livebearers and reproduce easily, making them a great choice for a no-filter tank.
- Tank Size: 5-10 gallons (19-38 liters)
- Care Level: Easy
- Adult Size: 0.6-2 inches (1.5-5 cm)
- Temperature: 72-82°F (22-28°C)
- Diet & Feeding: Omnivorous, enjoys a varied diet of flakes, pellets, frozen, and live foods
- Lifespan: 2-3 years
- Behavior: Peaceful, schooling fish that should be kept in groups
While guppies can survive without a filter, to ensure their health, provide plenty of live plants and clean at least 25% of the water every week. Regular water changes will help keep ammonia levels in check, making it easy to maintain a healthy home for your guppies.
Endler’s Livebearer
Endler’s Livebearers, closely related to guppies, are an increasingly sought-after species due to their vibrant colors and small size. Their hardy nature makes them a suitable option for no-filter tanks.
- Tank Size: 5-10 gallons (19-38 liters)
- Care Level: Easy
- Adult Size: 0.8-1.2 inches (2-3 cm)
- Temperature: 72-80°F (22-27°C)
- Diet & Feeding: Omnivorous, enjoys a varied diet of flakes, pellets, and live or frozen foods
- Lifespan: 2-3 years
- Behavior: Peaceful, shoaling fish that should be kept in groups
Endler’s Livebearers can live without a filter, but to maintain their health and happiness, include a mix of live plants and weekly water changes. Ensuring a clean environment without ammonia spikes is essential, so make sure you keep an eye on the water parameters to provide the best home for your Endler’s Livebearers.
Zebra Danios
Zebra Danios are renowned for their hardiness, making them ideal “starter” fish for beginner aquarists and no-filter tanks. Their distinct black and white stripes also make for an attractive addition to any aquarium.
- Tank Size: 10-20 gallons (38-76 liters)
- Care Level: Easy
- Adult Size: 1.5-2 inches (4-5 cm)
- Temperature: 65-77°F (18-25°C)
- Diet & Feeding: Omnivorous, versatile diet of flakes, pellets, and live or frozen foods
- Lifespan: 3-5 years
- Behavior: Peaceful, schooling fish best kept in groups of 6 or more
While Zebra Danios can live without a filter, maintaining good water quality is still essential for their wellbeing. Incorporate live plants in your tank and perform regular water changes to provide your Zebra Danios a safe and healthy environment.
White Cloud Mountain Minnows
White Cloud Mountain Minnows are another excellent choice for a no-filter tank, thanks to their adaptability and small size. They are a hardy and peaceful species, perfect for nano tanks and community setups.
- Tank Size: 10-15 gallons (38-57 liters)
- Care Level: Easy
- Adult Size: 1.5 inches (3.8 cm)
- Temperature: 64-72°F (18-22°C)
- Diet & Feeding: Omnivorous, enjoys a diet of flakes, pellets, and live or frozen foods
- Lifespan: 3-5 years
- Behavior: Peaceful, schooling fish that thrive in groups of 6 or more
For a healthy no-filter tank with White Cloud Mountain Minnows, incorporate plenty of live plants to assist with natural filtration, and maintain consistency in water parameters with regular water changes. These simple steps will ensure a thriving environment for your White Cloud Mountain Minnows.
Mosquito Rasboras
Mosquito Rasboras, also known as Boraras Brigittae, are tiny, colorful fish that add a pop of vibrancy to any aquarium. Their small size and hardiness make them suitable for no-filter setups.
- Tank Size: 5-10 gallons (19-38 liters)
- Care Level: Easy
- Adult Size: 0.7-1 inches (1.8-2.5 cm)
- Temperature: 74-82°F (23-28°C)
- Diet & Feeding: Omnivorous, needs a diet of small-sized flakes, pellets, and live or frozen foods
- Lifespan: 4-8 years
- Behavior: Peaceful, shoaling fish that prefer to be in groups
For a successful no-filter tank with Mosquito Rasboras, include a variety of live plants to assist with natural filtration and perform regular water changes to maintain optimal water quality. By creating a stable, clean environment, your Mosquito Rasboras will thrive.
Platy Fish
Platy Fish are a fantastic choice for no-filter tanks, as they are highly adaptable and require low maintenance. Their vibrant colors and active behavior make them an enjoyable addition to any aquarium.
- Tank Size: 10-20 gallons (38-76 liters)
- Care Level: Easy
- Adult Size: 1.5-2.5 inches (3.8-6.4 cm)
- Temperature: 70-80°F (21-27°C)
- Diet & Feeding: Omnivorous, enjoys a varied diet of flakes, pellets, and live or frozen foods
- Lifespan: 3-4 years
- Behavior: Peaceful, lively, and ideal for community tanks
To maintain a healthy no-filter tank with Platy Fish, incorporate live plants to assist in natural filtration and regularly change at least 25% of the water. These measures will help ensure excellent water quality, creating a perfect environment for your Platy Fish to thrive in.
Goldfish (smaller fancy varieties)
Smaller fancy varieties of goldfish, such as the Ryukin and Oranda, are beautiful and hardy fish that can adapt to no-filter tanks. They have unique physical features and can be an attractive addition to your home aquarium.
- Tank Size: 20-30 gallons (76-114 liters) for one fish, plus extra 10-20 gallons (38-76 liters) for each additional fish
- Care Level: Easy to Moderate
- Adult Size: 4-7 inches (10-18 cm), depending on the variety
- Temperature: 65-75°F (18-24°C)
- Diet & Feeding: Omnivorous, requires a diet of specialized goldfish flakes or pellets, and live or frozen foods
- Lifespan: 10-15 years
- Behavior: Peaceful, ideal for community tanks with similar-sized, non-aggressive tankmates
While these goldfish can survive in a no-filter setup, it is essential to commit to regular water changes and provide an excellent diet. Adding live plants and performing frequent water tests will also help in maintaining a stable and healthy environment for your goldfish.
Sparkling Gourami
Sparkling Gouramis, also known as Pygmy Gouramis, are an excellent option for no-filter tanks. Their small size, intriguing coloration, and ability to adapt to varying water conditions make them quite popular.
- Tank Size: 5-10 gallons (19-38 liters)
- Care Level: Easy
- Adult Size: 1.4 inches (3.5 cm)
- Temperature: 77-82°F (25-28°C)
- Diet & Feeding: Omnivorous, enjoys a well-balanced diet of flakes, pellets, and live or frozen foods
- Lifespan: 5-8 years
- Behavior: Largely peaceful, prefer to be in a group, may show territorial behavior during breeding
To care for Sparkling Gouramis in a no-filter tank, add live plants to aid in natural filtration and enhance water quality. Routinely change at least 20-30% of the water and monitor water parameters to ensure that your Sparkling Gouramis thrive in their environment.
Rice Fish
Rice Fish, also known as Medaka or Oryzias latipes, are one of those fascinating aquarium fish species known for their ability to adapt and thrive in diverse environments. Being able to tolerate varying water conditions makes them relatively easy to care for and a popular choice for aquarium hobbyists.
- Tank Size: 10 gallons (38 liters)
- Care Level: Easy
- Adult Size: 1.5 inches (3.8 cm)
- Temperature: 68-79°F (20-26°C)
- Diet & Feeding: Omnivores; can be fed a diet of high-quality flake food, pellets, and live or frozen foods such as brine shrimp or daphnia
- Lifespan: 3-5 years
- Behavior: Peaceful; suitable for community tanks, preferably kept in small groups
Rice Fish are perfect for those looking for a hardy species that does not require a filter, which is due to their ability to survive in slow-moving or stagnant water in the wild. With their attractive appearance, active demeanor, and compatibility with other peaceful fish, Rice Fish make for a delightful addition to any aquarium.
What are the Benefits of Filters for Aquariums?
A filter is an essential piece of equipment for maintaining a healthy aquarium. It plays a crucial role in the well-being of your aquatic friends. Let’s take a look at some of the benefits of filters for aquariums.
- Removes waste: A filter helps keep your tank clean by removing uneaten food, fish waste, and debris, preventing the buildup of harmful ammonia and nitrites.
- Maintains water quality: Filters play a crucial role in maintaining optimal water quality, ensuring a safe and healthy environment for your fish. They help stabilize pH levels, remove harmful substances, and maintain the right temperature.
- Promotes good bacteria growth: Beneficial bacteria aid in breaking down harmful waste into less toxic forms. Filters provide these bacteria with a place to grow and thrive.
- Enhances water circulation: Filters create water movement, ensuring proper oxygenation and even distribution of heat, reducing temperature and pH fluctuations.
- Prevents algae buildup: By removing excess nutrients and waste, filters help keep algae growth in check, ensuring a clean and attractive aquarium.
Despite these benefits, some aquarium fish species can still adapt to living without a filter.
How to Setup and Maintain a Fish Tank Without a Filter?
Setting up and maintaining a fish tank without a filter can be more challenging, but it’s not impossible. Follow these tips to create a healthy environment for your fish:
- Choose low maintenance fish: Opt for fish that are hardy and adaptable, requiring minimal filtration, like guppies and bettas. These fish have a low bioload, producing lesser waste.
- Plant your tank: Aquatic plants help in consuming waste and excess nutrients, providing essential water filtration. Choose fast-growing plants such as java moss, anubias, and hornwort.
- Moderate feeding: Overfeeding your fish leads to increased waste production, keeping portions small and removing any uneaten food will help maintain water quality.
- Water changes: Regular water changes are crucial for maintaining water quality in a tank without a filter. Change about 25-30% of the water weekly.
- Test water parameters: Monitor water temperature, pH levels, ammonia, and nitrite levels to ensure a healthy aquarium environment.
- Use air stones or sponge filters: If possible, use air stones or sponge filters to promote water circulation and oxygenation, improving the overall water quality.
How Does Filtration Affect Aquarium Fish Lifespan?
Filtration plays a significant role in maintaining the overall health and well-being of the fish in your aquarium. While some fish species can adapt to living without a filter, it’s essential to consider how the lack of filtration can impact their lifespan.
- Water quality: As filters help maintain water quality by removing debris and harmful waste, the absence of filtration can lead to increased stress on the fish, resulting in a shorter lifespan.
- Stress: Fish living in a tank without a filter might experience higher levels of stress due to fluctuations in water parameters and increased waste. Stress can negatively affect their immune system, making them more susceptible to diseases and shortening their lifespan.
- Disease: Poor water quality increases the risk of bacterial and parasitic infections, which can quickly spread and impact the well-being of all the inhabitants of the tank, potentially reducing their lifespan.
However, it’s worth noting that proper care, maintenance, and water changes can help prolong the lifespan of fish in a tank without a filter. To ensure the longest, healthiest life possible for your fish, choose the right species for your tank and be diligent in maintaining its environment.
Conclusion
In summary, the diversity and beauty of non-filter-dependent aquarium fish species are well worth exploring. Which of these ten unique fish species would you consider adding to your own tank? Let us know in the comments below!
