Shine Bright Like a Diamond Tetra

Shine Bright Like a Diamond Tetra

If you're looking for a fish that adds sparkle and elegance to your aquarium, the Diamond Tetra (Moenkhausia pittieri) is a must-have. Known for its shimmering silver body that glints like a diamond under the light, this peaceful and vibrant species is sure to captivate your attention. Native to South America, Diamond Tetras are a great choice for both beginners and experienced aquarists. In this care guide, we’ll walk you through everything you need to know to keep your Diamond Tetra healthy and happy, from water conditions to feeding, tank mates, and troubleshooting.

Water Parameters: Setting the Right Conditions

Diamond Tetras are native to the clear, acidic waters of the rivers in South America, where they thrive in stable, clean environments. To ensure your fish stay healthy, it’s important to recreate these conditions as closely as possible.

  • Temperature: 22–28°C. These fish thrive in warmer waters, so maintaining a stable temperature is key to their well-being.
  • pH: 5.5–7.0. A slightly acidic to neutral pH helps them feel at home, mimicking their natural habitat.
  • Hardness: 2–12 dGH. Soft to moderately hard water is ideal for keeping them healthy.

Why are these parameters important? Stable water temperature, pH, and hardness ensure that your Diamond Tetras stay comfortable and stress-free. Sudden changes in these conditions can lead to health problems, so consistency is key.

Tank Size and Setup: Creating the Perfect Home

Diamond Tetras are small, growing to around 5 cm in length, but they still require space to swim and feel comfortable. A minimum tank size of 60 litres is recommended for a small school of these fish. These tetras are social creatures and do best when kept in groups of 6 or more.

Tank Setup Tips:

  • Swimming Space: While Diamond Tetras are small, they are active swimmers, so providing plenty of open space in the middle and upper areas of the tank will allow them to thrive.
  • Aquascaping: Adding plants such as Amazon sword or Java moss will provide cover and help make the fish feel secure. Use a dark substrate like fine gravel or sand to enhance their natural shimmer.
  • Water Flow: These tetras prefer moderate water flow, which can be achieved with a gentle filter. Avoid strong currents, as it can stress the fish out.

Tank Mates: Peaceful Companions

Diamond Tetras are calm, peaceful fish that do well in community tanks with other gentle species. Since they are social fish, it’s important to keep them in groups, which helps them feel safe and reduces stress.

Ideal Tank Mates:

  • Other Tetra species (e.g., Neon Tetras, Ember Tetras)
  • Corydoras catfish
  • Guppies and peaceful Gouramis
  • Small peaceful Rasboras

Avoid keeping Diamond Tetras with aggressive or fin-nipping fish, such as bettas or barbs, as these can cause stress and injury.

Diet: What to Feed Your Diamond Tetra

Diamond Tetras are omnivores, which means they eat both plant and animal matter. To keep your fish healthy and vibrant, it’s important to offer a balanced diet.

Feeding Tips:

  • Foods: Provide high-quality flake food as a staple, supplemented with occasional frozen or live foods such as brine shrimp, daphnia, or bloodworms. They also enjoy algae wafers and small blanched vegetables like spinach or zucchini.
  • Feeding Frequency: Feed your Diamond Tetras once or twice a day, offering only as much food as they can consume in 2–3 minutes.
  • Portion Size: Be careful not to overfeed, as uneaten food can pollute the water and lead to health issues.

Common Mistakes: What to Avoid

Even experienced aquarists can make a few mistakes when caring for Diamond Tetras. Here are some common errors and how to avoid them:

  • Poor Water Conditions: Diamond Tetras are sensitive to changes in water quality. Regular water changes (around 20% every two weeks) and monitoring your tank’s parameters will help keep them healthy.
  • Overcrowding: While they are small, Diamond Tetras still need space. Stick to the recommended tank size and group size to prevent overcrowding and stress.
  • Feeding Incorrectly: Offering too much dry food or not providing a varied diet can negatively affect your fish’s health. A mix of flakes, live, and frozen foods is ideal.

Troubleshooting: Signs of Stress or Illness

Even with the best care, your Diamond Tetra may show signs of stress or illness. Here’s what to watch for:

  • Behavioral Changes: If your Diamond Tetra is swimming erratically, hiding more than usual, or not eating, it could be a sign of poor water quality or stress. Check your tank’s parameters and ensure everything is stable.
  • Physical Changes: Faded colors, frayed fins, or abnormal swimming behavior could indicate illness. If you notice these signs, isolate the affected fish and consult an expert or veterinarian if necessary.
  • Loss of Appetite: A lack of appetite can be caused by stress, illness, or water quality problems. Ensure the water is clean and the tank mates are compatible.

Visit Bay Aquatics for Everything You Need!

If you want to create the ideal home for your Diamond Tetras, visit Bay Aquatics. We offer everything you need to maintain the perfect environment for these stunning fish, from high-quality food to aquarium decor and expert advice. Visit us today to learn more about how to keep your Diamond Tetra healthy, happy, and shining bright in your tank!


By following these easy care tips, your Diamond Tetras will thrive and continue to dazzle with their bright, shimmering colors. These beautiful, peaceful fish make a great addition to any aquarium, and with the right care, they’ll shine bright for years to come!

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