How Many Angelfish Should Be Kept Together? - "File:Freshwater angelfish biodome.jpg" by mendel is licensed under CC BY-SA 1.0.
How Many Angelfish Should Be Kept Together? - "File:Freshwater angelfish biodome.jpg" by mendel is licensed under CC BY-SA 1.0.


Angelfish (Pterophyllum scalare) are among the most iconic and beloved freshwater fish in the aquarium hobby. With their elegant appearance and captivating behavior, angelfish have become a popular choice for aquarists of all experience levels. However, a common question that arises is: how many angelfish should be kept together in an aquarium? Answering this question requires careful consideration of various factors, including tank size, gender ratio, and individual temperament. In this guide, we will explore the ideal setup for an angelfish aquarium and discuss the factors to consider when determining the appropriate number of angelfish to keep together.

Appearance and Behavior

Angelfish (Pterophyllum scalare) are iconic freshwater fish known for their striking appearance and graceful demeanor. Here’s a detailed overview of their appearance and behavior:


  1. Body Shape: Angelfish have a distinctive triangular body shape with elongated fins. Their bodies are laterally compressed, giving them a sleek and elegant appearance.
  2. Finnage: One of the most notable features of angelfish is their long, flowing fins. They have two dorsal fins, one anal fin, and a trailing caudal fin. These fins add to their regal appearance and contribute to their graceful swimming motion.
  3. Coloration: Angelfish come in various color variations, including silver, black, marbled, and gold. The most common coloration consists of a silver body with vertical black stripes. Marbled varieties display intricate patterns of black, white, and silver, while gold angelfish have a vibrant golden hue.
  4. Size: Adult angelfish can reach lengths of up to 6 inches (15 centimeters) from tip to tip, including their fins. However, their size may vary depending on factors such as genetics, diet, and tank conditions.


  • Graceful Swimmers: Angelfish are known for their graceful and deliberate swimming motion. They glide effortlessly through the water, using their fins to steer and maneuver around obstacles.
  • Territorial Behavior: Angelfish can exhibit territorial behavior, especially during breeding. They may establish territories within the aquarium and defend them from perceived threats. This behavior can lead to aggression towards other fish that intrude upon their space.
  • Social Hierarchy: In a group setting, angelfish often establish a social hierarchy. Dominant individuals may assert their authority over subordinate fish through displays of aggression or dominance rituals. It’s essential to provide plenty of hiding places and visual barriers to minimize aggression among angelfish.
  • Breeding Behavior: When conditions are favorable, angelfish will display courtship behavior and form pairs for breeding. During courtship, they may engage in elaborate displays, including fin flaring and circling each other. Once a pair forms, they may become more aggressive towards other fish in the aquarium, especially if they perceive them as threats to their offspring.
  • Interactive with Their Environment: Angelfish are curious by nature and will often investigate their surroundings. They may interact with tank decorations, plants, and other tank inhabitants. Providing a stimulating environment with plenty of hiding places and structures to explore can help keep angelfish active and engaged.

Overall, angelfish are captivating freshwater fish cherished by aquarium enthusiasts for their beauty and intriguing behavior. With proper care and attention to their needs, they can thrive in home aquariums and bring joy to their owners for many years.

How Many Angelfish Should Be Kept Together?

Determining how many angelfish should be kept together involves considering various factors, including aquarium size, gender ratio, and individual temperament. Here’s a comprehensive guide:

Aquarium Size

  • Angelfish require ample space to thrive due to their size and swimming behavior.
  • A minimum tank size of 20 gallons (75 liters) is recommended for a small group of angelfish. However, larger tanks are preferable, especially for multiple angelfish.
  • As a general rule, provide at least 10 gallons (40 liters) of water per angelfish to accommodate their adult size and swimming activity.

Gender Ratio

  • Maintaining a balanced gender ratio can help minimize aggression and promote harmonious interactions among angelfish.
  • For a community tank, aim for a ratio of one male to two or three females. This ratio reduces competition for breeding partners and spreads out potential aggression.
  • Keeping multiple females can help disperse aggression from dominant males, as they may focus their attention on courting and protecting a mate.

Individual Temperament

  • Each angelfish has its own personality and temperament, which can influence tank dynamics.
  • Some angelfish may be more aggressive or territorial than others. It’s essential to observe their behavior and provide adequate hiding spots and visual barriers to reduce stress and aggression.
  • Avoid keeping overly aggressive or dominant individuals with smaller or more docile fish species, as they may intimidate or harass them.
How Many Angelfish Should Be Kept Together? - "File:Freshwater angelfish biodome.jpg" by mendel is licensed under CC BY-SA 1.0.
How Many Angelfish Should Be Kept Together? – “File:Freshwater angelfish biodome.jpg” by mendel is licensed under CC BY-SA 1.0.

Aquarium Setup

Setting up an aquarium for angelfish requires careful consideration of their natural habitat, water parameters, tank size, decor, and filtration. Here’s a step-by-step guide to setting up an ideal aquarium for angelfish:

Tank Selection

  • Choose a tank size appropriate for the number of angelfish you plan to keep. A larger tank is preferable, with a minimum size of 20 gallons (75 liters) for a small group of angelfish.
  • As mentioned, a good rule of thumb is one adult angelfish per 10 gallons (40 liters) of water.
  • Consider a tank with dimensions that allow for vertical swimming space, as angelfish have tall bodies and elongated fins.


  • Use a substrate such as fine gravel or sand, which mimics the natural environment of angelfish.
  • Dark-colored substrates can enhance the coloration of angelfish and provide a visually appealing contrast.

Water Parameters

  • Angelfish prefer slightly acidic to neutral water conditions with a pH range of 6.5 to 7.5.
  • Maintain a water temperature between 75°F to 82°F (24°C to 28°C), as angelfish are tropical fish.
  • Monitor ammonia, nitrite, and nitrate levels regularly and perform water changes as needed to maintain water quality.


  • Install a reliable filtration system capable of handling the bioload of the tank and providing adequate water circulation.


  • Incorporate live or artificial plants to provide shelter, hiding spots, and visual barriers for angelfish.
  • Choose plants that are compatible with the lighting and water parameters of the tank. Recommended plants include Amazon swords, Java ferns, Anubias, and Vallisneria.
  • Include driftwood, rocks, and caves to create natural hiding places and territorial boundaries for angelfish.
  • Arrange the decor to create separate territories and swimming areas, allowing angelfish to establish their hierarchy and reduce aggression.


  • Provide moderate lighting suitable for the growth of live plants and to showcase the colors of angelfish.
  • Use a timer to simulate a natural day-night cycle, with approximately 8 to 10 hours of light per day.

Water Quality Maintenance

  • Perform regular water changes of 25% to 50% every 1-2 weeks to remove accumulated waste and maintain water quality.
  • Vacuum the substrate during water changes to remove debris and uneaten food.

Cycling the Tank

  • Before adding angelfish, cycle the aquarium to establish beneficial bacteria that break down ammonia and nitrite.

Acclimating Angelfish

  • When introducing angelfish to the tank, acclimate them slowly to prevent stress and shock.
  • Float the bag containing the angelfish in the tank for 15-20 minutes to equalize the temperature. Then, gradually add small amounts of tank water to the bag over a period of 30-60 minutes before releasing the fish into the tank.

By following these steps and providing a well-equipped and carefully maintained aquarium, you can create a suitable environment for angelfish to thrive and display their natural behaviors. Regular observation and adjustments to tank conditions will help ensure the health and well-being of your angelfish community.


In conclusion, creating a harmonious and thriving angelfish aquarium involves careful planning and consideration of their specific needs and behaviors. Understanding how many angelfish should be kept together is essential for maintaining a healthy and balanced aquatic environment. By providing adequate space, proper tank decor, and a balanced gender ratio, aquarists can ensure the well-being and happiness of their angelfish community. Remember to observe your angelfish regularly and make adjustments to tank conditions as needed to promote their health and longevity. With the right setup and attention to detail, keeping angelfish can be a rewarding experience for any aquarium enthusiast.