The Harlequin Rasbora, scientifically known as Trigonostigma heteromorpha, belongs to the Cyprinidae family. Native to Southeast Asia, particularly in Thailand, Malaysia, and Singapore, these small, schooling fish are admired for their vibrant colors and distinctive triangular pattern. Harlequin Rasboras have a typical cyprinid genome and belong to the evolutionary line adapted to the freshwater habitats of their native region. Their peaceful nature and striking appearance make them a popular choice for community aquariums.

Summary of Aquatic Life:
Harlequin Rasboras are characterized by their iridescent orange bodies and a prominent black triangular patch. These fish are shoaling by nature and thrive in groups, displaying enhanced colors and social behaviors in a well-maintained aquarium. They prefer densely planted tanks with soft, slightly acidic water. A varied diet consisting of high-quality flakes, pellets, and live or frozen foods like brine shrimp and daphnia contributes to their overall well-being.

Creating a Happy and Healthy Environment:
1. Tank Size: Provide a tank of at least 10 gallons for a small group, with a longer tank being more suitable for their swimming habits.
2. Water Parameters: Maintain a temperature between 72-79°F (22-26°C) and a pH level between 6.0-7.8.
3. Filtration: Efficient filtration to ensure clean and well-oxygenated water.
4. Substrate and Decor: Use soft substrate and include plants, driftwood, and floating vegetation for a natural habitat.
5. Lighting: Use subdued lighting to mimic their native shaded environments.
6. Feeding: Offer a varied diet including high-quality flake foods, pellets, live or frozen foods like brine shrimp, and occasional vegetable matter.

Compatible Aquatic Life:

Fish:
1. Neon Tetra (Paracheirodon innesi): Similar in size and temperament, creating a harmonious community.
2. Cardinal Tetra (Paracheirodon axelrodi): Small, colorful tetras compatible with Harlequin Rasboras.
3. Betta Fish (Betta splendens): Peaceful bettas can coexist in a community setup with Harlequin Rasboras.
4. Pygmy Corydoras (Corydoras pygmaeus): Small, bottom-dwelling catfish suitable for the same environment.
5. Dwarf Gourami (Trichogaster lalius): Peaceful gouramis that complement the vibrant colors of Harlequin Rasboras.

Crustaceans:
1. Amano Shrimp (Caridina multidentata): Non-aggressive shrimp suitable for larger setups.
2. Red Cherry Shrimp (Neocaridina davidi): Colorful and compatible with Harlequin Rasboras.
3. Ghost Shrimp (Palaemonetes spp.): Inexpensive and harmless tank cleaners.
4. Bamboo Shrimp (Atyopsis moluccensis): Larger filter-feeding shrimp suitable for larger tanks.
5. Vampire Shrimp (Atya gabonensis): Peaceful filter-feeding shrimp.

Bugs:
1. Daphnia: Nutrient-rich live food for Harlequin Rasboras.
2. Mosquito Larvae: Natural and occasional live food.
3. Fruit Flies: Small, flying insects for variety in the diet.
4. Bloodworms: High-protein live or frozen food.
5. Brine Shrimp: Excellent for conditioning and variety in diet.

Plants:
1. Java Moss (Taxiphyllum barbieri): Provides hiding spots and breeding grounds.
2. Anubias (Anubias spp.): Attachable to driftwood, providing cover for Harlequin Rasboras.
3. Cryptocoryne (Cryptocoryne spp.): Rooted plants adding to the overall habitat.
4. Water Wisteria (Hygrophila difformis): Fast-growing plant for water quality and aesthetics.
5. Duckweed (Lemna minor): Floating cover for a more secure environment.

Amphibians:
1. Dwarf African Clawed Frog (Hymenochirus spp.): Peaceful aquatic frogs.
2. African Dwarf Frog (Hymenochirus curtipes): Small, aquatic frogs compatible with Harlequin Rasboras.
3. Fire-Bellied Newt (Cynops spp.): Semi-aquatic newts suitable for a shared habitat.
4. Oriental Fire-Bellied Toad (Bombina orientalis): Colorful toads for a unique aquatic setup.
5. Mudskipper: Brackish water amphibian, providing a dynamic ecosystem.

These considerations contribute to a diverse and balanced aquatic community, ensuring the well-being of Harlequin Rasboras and their tankmates.