Japanese Trapdoor Snail

Cipangopaludina malleata

FreshwaterSnail

Care at a glance

Temperature: 64–77°F (18–25°C)
pH: 6.5–8.0
Adult size: 2 in (5 cm)
Minimum tank: 8 gal (30 L)
Temperament: Peaceful
Social behavior: Solitary
Swim level: Bottom
Difficulty: Easy
Breeding: Medium
Rarity: Very rare
Origin: Japan
Family: Viviparidae

Overview

Japanese trapdoor snails are hardy, peaceful grazers that work over the glass, plants, and substrate for algae, biofilm, and waste without touching healthy plants. They are calm and get along with fish, shrimp, and other snails, and a single snail needs no company. They tolerate a wide range and even cool water, which makes them a common pick for unheated tanks and ponds. Keep the water on the harder side to support the shell, and keep copper out, since it harms snails. They give birth to live young slowly, so they will not swamp a tank. A tank of 30 liters or more is plenty.

In the wild

This snail comes from Japan and nearby East Asia, where it lives in ponds, rice paddies, ditches, and slow rivers with muddy bottoms. Those waters swing with the seasons, so the snail is used to cool as well as mild temperatures and adapts to a tank held anywhere from about 18 to 25 c. A pH from 6.5 to 8 suits it, and it does best with enough minerals to keep the shell solid. A soft substrate, some plants, and gentle filtration recreate the calm, food-rich habitat it prefers.

Good to know

Cipangopaludina malleata is a member of the Viviparidae, the family of livebearing river snails that gives the trapdoor snails their name. It grows to around 5 cm with a rounded, olive to brown shell sealed by a horny operculum. True to the family, it does not lay eggs: the female broods her young inside and delivers small, fully formed snails a few at a time. That steady but modest rate makes home breeding straightforward without ever becoming a nuisance.

Did you know

The trapdoor name comes from the operculum, a tough plate on the snail's foot that seals the shell mouth like a door when it withdraws. It guards against drying out and against predators, and it also lets the snail ride out cold spells that would stop most tropical snails.