Guppies vs. Medaka: Which Is Easier to Keep? A Thorough Comparison
A thorough comparison of guppies and medaka, popular for aquarium beginners. We explain the key points for choosing between them, covering difficulty of care, required equipment, ease of breeding, running costs, and whether outdoor keeping is possible.
Key Takeaways
A thorough comparison of guppies and medaka, popular for aquarium beginners. We explain the key points for choosing between them, covering difficulty of care, required equipment, ease of breeding, running costs, and whether outdoor keeping is possible.
Related Species
When you decide to start an aquarium, guppies and medaka are the first fish that come to mind. Both are small, easy to keep, and popular species that offer the pleasure of breeding, but when you actually raise them, their individual characteristics are quite different. Equipment costs, maintenance effort, ways to enjoy different varieties—each has its own field of expertise. In this article, we'll conduct a multifaceted comparison of guppies and medaka so that first-time fish keepers can choose with confidence.
Basic Specs and Behavioral Differences
Let's first understand the basic profile of both fish.
Guppies are a representative tropical fish, native to Central and South America. They are about 3–5 cm in body length, with males displaying distinctively large, flowing tail fins. Their lifespan is relatively short at 1–2 years, but their breeding cycle is correspondingly rapid, producing fry approximately once a month. Being ovoviviparous (eggs hatch inside the mother's body and fry are born live) is another characteristic that gives them high fry survival rates.
Medaka are temperate fish that have inhabited Japanese paddies and streams since ancient times. They measure about 3–4 cm in body length and live 2–3 years, longer than guppies. They are oviparous and spawn almost daily, but since parent fish eat the eggs, breeding requires the effort of collecting and isolating eggs.
This "difference in origin" significantly impacts the breeding environment. Guppies, being tropical, are sensitive to low temperatures and cannot survive Japanese winters outdoors. Conversely, medaka, naturally adapted to Japan's climate, can be kept year-round even in outdoor biotopes. For a comparison of indoor and outdoor medaka care, see also Indoor vs. Outdoor Care: What's the Best Environment for Medaka?
Equipment and Running Costs
Equipment needed for guppies - Aquarium (minimum 30 cm, preferably 45–60 cm) - Hang-on or undergravel filter - Thermostat-equipped heater (maintaining 22–26°C) - Lighting (especially important if growing aquatic plants)
The heater runs up several hundred yen per month in electricity costs, and when combined with filter media replacements and other expenses, the monthly running cost comes to approximately ¥500–1,500. Including the initial investment, you should budget around ¥10,000 for the minimum setup.
