How Many Betta Fish Can You Put In A 33-Gallon Tank?

How Many Betta Fish Can You Put In A 33-Gallon Tank?

If you’re a fish enthusiast, you may be wondering how many betta fish you can safely keep in a 33-gallon tank. Betta fish, also known as Siamese fighting fish, are known for their vibrant colors and beautiful fins.

While they can be territorial, they can also thrive in a community tank if certain conditions are met. In this article, we will explore the factors that determine the number of betta fish you can keep in a 33-gallon tank and provide some tips to ensure their well-being.

Key Takeaway: Betta Fish in a 33-Gallon Tank

Before we dive into the details, let’s summarize the key points for quick reference:

Tank SizeMaximum Number of Betta Fish
33 gallonsUp to 4-5 betta fish

Now that you have a general idea, let’s delve deeper into the important factors to consider when determining how many betta fish can thrive in a 33-gallon tank.

Factors That Determine the Number of Betta Fish

1. Tank Size

A 33-gallon tank provides ample space for betta fish to move around and establish territories. The larger the tank, the more fish it can accommodate. However, it’s important to remember that bettas are still territorial, so providing plenty of hiding spots and visual barriers is crucial. This prevents aggression and allows each fish to have its own space.

2. Compatibility

Compatibility is crucial when adding betta fish to a community tank. While bettas can be kept with other species, it’s important to choose tank mates that are peaceful and have similar requirements in terms of water temperature and pH levels. Fish that are small, non-aggressive, and not fin nippers are often good companions for bettas.

3. Gender

If you’re planning to keep multiple betta fish in a community tank, it’s essential to have a proper male-to-female ratio to avoid aggression. In general, it is recommended to have one male betta and multiple females. Males should not be housed together, as they are likely to fight and injure each other.

4. Filtration and Water Quality

Maintaining good water quality is vital for the health and well-being of all fish. A 33-gallon tank requires a robust filtration system to remove waste and maintain optimal oxygen levels. Performing regular water changes and monitoring water parameters such as temperature, pH, and ammonia levels are necessary to ensure the water remains clean and suitable for the fish.

Tips for Keeping Betta Fish in a 33-Gallon Tank

To ensure the happiness and well-being of your betta fish in a 33-gallon tank, here are some tips to consider:

  • Provide hiding spots and visual barriers such as plants, rocks, or ornaments to create separate territories for each fish.
  • Maintain a consistent water temperature between 78-80°F (25-27°C) as bettas are tropical fish.
  • Avoid adding aggressive or fin-nipping tank mates.
  • Feed your bettas a balanced diet of high-quality betta pellets, supplemented with occasional live or frozen foods.
  • Monitor water parameters regularly and perform regular water changes to maintain water quality.
  • Observe the behavior of your bettas closely and be prepared to make adjustments if any signs of aggression or stress are noticed.

By following these tips and providing a comfortable environment, you can create a thriving community tank where your betta fish can coexist peacefully.


In a 33-gallon tank, you can comfortably keep up to 4-5 betta fish, provided you take into consideration the tank size, compatibility with other species, and gender ratios, and maintain optimal water quality. It’s important to note that every betta fish is unique, and their compatibility may vary, so always keep a close eye on their behavior and make adjustments as needed. With proper care, your betta fish will flourish in their spacious and welcoming habitat. Happy fish keeping!