How to Build a Medaka Biotope — Recreating Natural Outdoor Habitats
Beginners guide to building a medaka biotope: container selection, substrate and plant placement, water management, and seasonal care.
Key Takeaways
Beginners guide to building a medaka biotope: container selection, substrate and plant placement, water management, and seasonal care.
Related Species
Medaka biotopes are a breeding style that recreates a natural aquatic environment in a small container. Without using pumps or filters, the ecosystem maintains water quality through aquatic plants and microorganisms—making it the breeding environment closest to medaka's natural ecology. Its visual beauty and the ability to enjoy medaka while experiencing seasonal changes are its greatest appeals.
Basic Concept of Biotopes
A biotope is a German word meaning "habitat for living organisms," referring to a small artificial ecosystem. In a medaka biotope, medaka, aquatic plants, microorganisms, and snails maintain a balanced environment through their interactions.
Medaka waste and uneaten food are broken down by bacteria, and the nutrients are absorbed by aquatic plants. Plants produce oxygen through photosynthesis, replenishing the oxygen needed for medaka respiration. When this cycle works well, water quality remains stable without a filter.
Choosing a Container
Biotope containers come in various options.
Water lily basin (suiren bachi): The standard biotope container. The ceramic texture creates a Japanese aesthetic and offers excellent heat retention. Choose one with a diameter of 40cm or larger and a capacity of 20 liters or more.
Plastic trough (toro bune): A plastic container used in construction work, offering affordability and large capacity. Large sizes of 40 or 60 liters allow breeding of many medaka and are suitable for reproduction. While simple in appearance, placing bricks or wood panels around it improves the landscape.
Styrofoam container: Extremely high insulation protects water temperature from summer heat and winter freezing. Black styrofoam containers make medaka body color appear darker, making them popular with breeders.
Wooden barrels or wine barrels: Atmospheric containers that suit Western-style gardens. However, choose ones coated with food-safe waterproof coating to prevent harmful substances from dissolving into the water.
The key consideration when choosing a container is water volume. Secure at least 10 liters minimum, ideally 20 liters or more. Greater water volume results in smaller fluctuations in temperature and water quality, creating a more stable environment for medaka.
