Japanese Trapdoor Snail Care: Size, Breeding, Diet, Lifespan

The Japanese Trapdoor Snail is a pond snail that loves to eat algae. But, these freshwater snails are omnivores, so they eat live foods, frozen foods, and other fish food as well. Other names include the Chinese Mystery Snails or Trapdoor Snails.

NameJapanese Trapdoor Snails
Common namesTrapdoor Snails, Chinese Mystery Snails
Scientific nameViviparus sp.
Tank size (minimal)10-gallons (~40 liters)
BreedingEasy. Slow
Size5 – 7 cm (2 – 3 inches)
Temperature18 to 25 C  (~66 – 78 F)
Optimal PH7.0 – 8.0 
Optimal GH6 – 18 
Optimal KH4 – 8 
TDS (optimal)100 – 250 
NitrateLess than 40 ppm
DietOmnivore / Algae eater
TemperamentPeaceful. Solitary
Life spanup to 10 years
Color FormBlack, brown, green,  with a large area of white.
Quick Notes about Japanese Trapdoor Snails

Photos of Japanese Trapdoor Snail


The Japanese Trapdoor Snail shell color can be shades of black, dark green, or olive green. There are some instances of dark brown, reddish-brown, and light brown as well.

It’s not unusual for shells to have large areas of white on the spire close to the apex. The texture is smooth with grooves that appear as the snail grows. They usually have three whorls but sometimes it can be more. The shell tapers off and becomes thinner the further away it is from the body.

There is usually a base color on the largest whorl and some different colored rings and textured lines that extend further up. They also have an operculum which serves as a trapdoor to protect them if they feel threatened.

japanese trapdoor snail babies
Japanese trapdoor snail babies


Japanese Trapdoor Snails are peaceful creatures. They spend most of the time exploring the tank in search of food. They are more active during the night and they get along with other peaceful aquarium pets.

These snails sometimes prefer to hide in their shells for long periods of time. You shouldn’t worry so long as the water parameters are ideal, chances are that they are resting.

Japanese trapdoor snails also tend to venture up to the water’s surface. A cover or a lower water level is good to keep them from crawling out of the tank.


The average size of adult Trapdoor Snails is 2 inches in length. They are one of the largest freshwater snails in the aquarium trade.


The average lifespan of Japanese Trapdoor Snails ranges from 5 to 10 years. To make sure these creatures live as long as possible you need to provide the best care possible.


Japanese Trapdoor Snails (Viviparus malleatus) is an omnivore. It will eat soft algae, plant matter, vegetables, fish food, frozen foods, and live foods. These algae eaters spend most of their time scavenging the fish tank for food. Of course, they prefer to eat algae but will chow down on what’s readily available.


Japanese Trapdoors are non-hermaphroditic. That means that each trapdoor snail is either a male or a female. They are live-bearers and breed slower than other snails. Females give birth to 6 to 20 babies at a time.

Japanese trapdoor snail breeding is easy. All you need is a male and female in a tank with optimal water parameters. Japanese trapdoor snails can start reproducing when the snails are at least a year old.

Tank Mates

The Japanese Trapdoor snail is peaceful, so it is best to keep them with other peaceful aquarium pets.

Freshwater aquarium fish like:

Other Snails:

Some species of aquarium shrimp:

Freshwater clams like the Asian Gold Clam. Do not keep them in fish tanks with Oscars and other cichlids, Goldfish or Aquarium Crayfish.

Japanese Trapdoor Snail Care

Live Plants

It’s best to keep Japanese Trapdoor Snails in aquariums with live aquarium plants. Live plants shed edible plant matter that snails love to eat. Once your snails are well-fed they tend not to eat the plants. Also, thick and hardy plants like Anubias are less likely to be targeted by snails as snacks.

Tank Size

The Japanese Trapdoor Snail can live in tanks as small as 10 gallons. Always make sure that your aquariums are not overstocked, are well filtered, and oxygenated.

Water Parameters

Water parameters for the trapdoor snail are a bit flexible. It’s one of the easier parts of caring for the snails. They are hardy and can survive various water conditions. To be on the safe side, try maintaining the following parameters:

  • Aquarium pH: 7.0 to 7.6
  • Temperature: 72 – 80 Degrees Fahrenheit.
  • Lighting: Regular community tank lighting.

How To Buy Healthy Trapdoor Snails

To buy healthy Japanese Trapdoor Snails, make sure that there are no cracks or holes in the shell. The snail should be stuck to hard surfaces or crawling on the tank bottom. There should be two eyes and tentacles. The operculum should be visible above their foot, near their backside

Do not buy snails that are motionless or upside down. Do not buy snails that are floating near the surface. These are signs that the snail is sick, dying, or already dead.

Frequently Asked Questions

Are Japanese trapdoor snails invasive?

Japanese trapdoor snails are illegal in some states and considered invasive in some areas. Always check with your local state laws and guidelines before collecting them.

Do Japanese trapdoor snails lay eggs?

Japanese Trapdoor Snails are live bearers, so they do not lay hard eggs on surfaces. Instead, they produce live baby snails.

How long do Japanese trapdoor snails live?

The average lifespan of Japanese Trapdoor Snails ranges from 5 to 10 years. To make sure these creatures live as long as possible you need to provide the best care possible.

How big do Japanese trapdoor snails get

Trapdoor Snails can grow quite large as adults. Many adult snails can grow up to 2 inches in length, making them one of the largest freshwater snails in the aquarium hobby.