Expert Guide : Fish for 5 gallon tank

In recent years, the world of aquarium keeping has seen a surge in the popularity of smaller tanks, with 5-gallon setups dominating the trend. These miniature aquatic ecosystems have found their way into homes, offices, and even classrooms, enthralling both enthusiasts and novices. You might wonder what is so tempting about the 5-gallon tank. Well, it’s not just about size; it’s about the endless opportunities it offers. In this comprehensive guide, we will explore the best fish for a 5-gallon tank, delve into setting up and maintaining the special habitat, discuss suitable plants, and even provide creative design ideas.



Advantages of a 5-gallon Tank

Before we crash into the specifics, let’s take a minute to appreciate the advantages of a 5-gallon tank. Grasping these benefits will help you make an informed decision and ensure the well-being of your aquatic pets.


Easier Water Parameter Stability

One of the prime advantages of a 5-gallon tank is its relative stability in terms of water parameters. Smaller volumes of water are less likely to cause drastic fluctuations in temperature and water chemistry, making it simpler for novices to maintain a healthy environment.


Diversity of Livestock

While a 5-gallon tank may seem limited in size, it’s surprising how many fish and other aquatic creatures can happily inhabit it. With the right choices, you can establish a dynamic and diversified aquatic community.


Design Potential

Small does not imply monotonous. The compact nature of a 5-gallon tank allows potential for innovative design. Whether you want to mimic a lush underwater forest or a tranquil Zen Garden, the options are infinite.


Best Fish for a 5-gallon Tank

Setting up a 5-gallon tank requires careful consideration while selecting the fish species. These pint-sized aquatic environments require fish that are compatible with limited space and can flourish in a smaller volume of water. Here’s a list of fish species that are ideal for a 5-gallon setup:


Betta Fish (Betta splendens)

Size: 2-3 inches

Temperament: Generally solitary, can be hostile toward other Betta fish.

Description: Betta fish are a current choice for small tanks due to their eye–catching colours and distinctive personalities. They come in a variety of hues and tail styles, making them a visually appealing addition to your tank. It’s important to note that Betta fish can live well in a 5-gallon tank, they should not be housed together unless you have a divided tank to prevent aggression.


Endler’s Livebearer (Poecilia wingei)

Size: 1-1.5 inches

Temperament: Peaceful and social, suitable for community tanks.

Description: Endler’s Livebearers are tiny, colourful fish that are perfect for small aquariums. They are active swimmers and can add a vivid dynamic to your 5-gallon tank. Consider keeping a small school of Endler’s Livebearers to create a charming appeal and zestful display in your tank.


Dwarf Corydoras (Corydoras habrosus)

Size: 1 inch

Temperament: Serene and gregarious, prefers the company of its kind.

Description: Dwarf Corydoras are tiny bottom-dwelling fish that are ideal for aquariums with limited space. They are known for their playful behaviour and can be a delight to watch as they explore the substrate. These fish appreciate a soft substrate and should be kept in groups of at least three to guarantee their well-being.


Scarlet Badis (Dario dario)

Size: 0.75-1 inch

Temperament: Generally kind, but males can be territorial with each other.

Description: The Scarlet Badis is a little, brightly coloured fish that adds a touch of elegance to your tank. They are relatively easy to care for and can prosper in a 5-gallon environment. Ensure that you provide plenty of hiding spots and vegetation for the Scarlet Badis to establish territories if you intend to retain multiple males.


White Cloud Mountain Minnow (Tanichthys albonubes)

Size: 1.5 inches

Temperament: Peaceful and schooling, should be kept in groups.

Description: These small, schooling fish are a great choice for a 5-gallon tank. They are hardy and come in various colour variations, adding vibrancy to your setup. White Cloud Mountain Minnows are social fish and should ideally be kept in groups of at least five to six individuals.


Setting Up a 5-gallon Aquarium

Now that you have an idea of the fish you can choose from, it’s time to dive into the process of setting up your 5-gallon aquarium. This step-by-step guide will ensure a smooth start for your miniature aquatic world.


Step 1: Gather Your Equipment

Before you begin, gather all the necessary equipment. You’ll need:

  • A 5-gallon aquarium tank with a secure lid.
  • A sufficient filter and heater (if necessary, depending on the fish species you choose).
  • Substrate (gravel or sand).
  • Decor and plants.
  • Water conditioner and a test kit.
  • Fish food appropriate for your chosen species.

Research your selected fish’s specific requirements, as some may need a heater to maintain the right temperature.


Step 2: Set Up the Tank

  1. Rinse the substrate thoroughly to get rid of any dust or debris.
  2. Add the substrate to the tank, sloping it gently backwards for more apparent depth.
  3. Place ornaments, pebbles, and plants, leaving room for swimming.
  4. Fill the tank with conditioned water, following the instructions on your water conditioner.
  5. Install the filter and heater, if necessary, and let them run for at least 24 hours to ensure they are working correctly.


Step 3: Cycle the Tank

Cycling is a crucial step that establishes a stable biological filter in your tank. It entails cultivating beneficial bacteria that convert poisonous ammonia into less toxic substances. To cycle your tank:

  1. Include a source of ammonia (fish food, liquid ammonia, or a starter fish).
  2. Test the water regularly for ammonia, nitrite, and nitrate levels.
  3. Once ammonia and nitrite levels spike and then drop to zero, and nitrates are present, your tank is cycled and ready for fish.


Step 4: Introduce Your Fish

When your tank is fully cycled, it’s time to introduce your plump-up fish. Habituate them to the tank’s temperature and water conditions by floating their bag in the tank for about 15-20 minutes. Then, carefully release them into their new home. Avoid adding all your fish at once; instead, stagger their introduction to prevent overwhelming the tank’s biological balance.


Step 5: Monitor and Maintain

Regularly check and maintain your tank:

  • Perform weekly water changes of about 20% to 25%.
  • Test water parameters regularly to ensure they remain within acceptable limits.
  • Feed your fish an appropriate diet, taking care not to overfeed.


5-Gallon Tank Plants

live plants in a 5-gallon tank not only enhances its aesthetic appeal but also provides several advantages. They assist in preserving the water quality, providing lurking spots for fish, and contributing to a more natural and balanced ecosystem. Here are some excellent plant options for your small aquarium:


Java Moss (Taxiphyllum barbieri)

 Java Moss is an undemanding and versatile plant that can be fastened to rocks or driftwood. It protects fry (baby fish) and small invertebrates while also filtering the water.


Marimo Moss Ball (Aegagropila linnaei)

Marimo Moss Balls are unique spherical algae that require minimum care. They are recognized for their whimsical look and are excellent nitrate absorbers. Gently roll the Marimo Moss Ball periodically to ensure even growth.


Dwarf Hairgrass (Eleocharis parvula)

 Dwarf Hairgrass is a fine, grass-like plant that creates a lush carpet in your tank. It thrives in well-lit environments and adds a touch of elegance.


Freshwater Species for Small Tanks

While fish are the stars of your 5-gallon tank, don’t forget about the other fascinating aquatic creatures that can thrive in this environment. Consider adding some of these non-fish species to your tank:


Cherry Shrimp

Cherry shrimp are small, vibrant, and easy to care for. They are superb scroungers and help keep your tank clean. Cherry shrimp are not only low-maintenance but also intriguing to observe as they go about their daily activities,” according to aquarist and shrimp enthusiast David Chen.


Nerite Snails

Nerite snails are known for their striking patterns and propensity for consuming algae. They are peaceful and won’t overpopulate your tank.


Maintaining a 5-gallon Ecosystem

Proper maintenance is key to the longevity and health of your 5-gallon tank. While small tanks offer several advantages, they can also present unique challenges that require careful attention.

Routine Checks

  • Monitor water temperature daily, especially if you have sensitive species.
  • Perform weekly water tests for ammonia, nitrites, and nitrates.
  • Check the equipment (filter, heater, lighting) regularly to ensure they are functioning correctly.

Water Changes

  • Aim for a weekly water change of 20% to 25% to remove waste and replenish essential minerals.
  • Use a siphon to vacuum the substrate during water changes to prevent the buildup of debris.


  • Be vigilant for signs of overfeeding, as excess food can lead to water quality issues.
  • Watch for any aggressive behaviour among fish species and provide hiding spots if needed.
  • Keep an eye out for signs of illness in your fish and address them promptly.

Design Ideas for 5-Gallon Tanks

Now that you’ve mastered the art of choosing fish, setting up your tank, and maintaining a balanced ecosystem, it’s time to let your creativity flow. Here are some design ideas to inspire your 5-gallon tank:


1. Zen Garden

Create a tranquil underwater Zen garden with smooth stones, minimalist decor, and a school of peaceful fish like White Cloud Mountain Minnows. Add a touch of elegance with Anubias Nana and Java Moss.


2. Underwater Jungle

Transform your tank into a bright rainforest with lush plants, driftwood, and vibrant Betta fish. Create layers of foliage and hiding spots for a lively and beautiful landscape.


3. Desert Oasis

Contrast the underwater world with a desert-themed setup. Use sand as substrate, add a few cacti-like decorations, and house Scarlet Badis or Endler’s Livebearers to create a unique ecosystem.


4. Fairytale Forest

Turn your 5-gallon tank into an enchanted forest with dense plantings, twisted branches, and tiny Dwarf Corydoras exploring the leaf litter.


5. Mini Reef

For those who love saltwater aesthetics, consider a nano-reef tank with colourful coral decorations and tiny marine fish like Gobies or Clownfish.



As you embark on your journey into the world of 5-gallon tanks, remember that responsibility and research are your best allies. By selecting the right fish, providing a suitable environment, and maintaining your mini-aquatic ecosystem, you can create a captivating and thriving underwater world. Whether you choose Betta Fish, Endler’s Livebearers, or Scarlet Badis, your 5-gallon tank has the potential to be a mesmerizing centerpiece in your home or office. Enjoy the adventure and may your aquatic companions flourish in their cozy new home.