: Extremely hardy "bulletproof" fish that are often used to start new tanks. Key Equipment for a Subtropical Tank

Buying —species that thrive in water temperatures between temperate and tropical (typically 64°F to 72°F)—is an increasingly popular choice for aquarists seeking hardy, energy-efficient setups. Because these fish often live in centrally heated homes without a heater, they are relatively inexpensive to maintain. Popular Subtropical Fish Species

When looking to buy, consider these common species known for their adaptability to cooler waters:

: Robust, attractive labyrinth fish related to bettas. They are adaptable but males can be aggressive toward each other.

: Colorful, hardy livebearers that actually do better at subtropical temperatures than standard tropical ones.

While you may save on heating, a proper environment still requires essential gear: Subtropical Fish Species | Tropical Fish Hobbyist Magazine

: Large, active barbs with a metallic sheen; they are peaceful and can even be kept with goldfish in large enough tanks.