Japanese Trapdoor Snails 101: Complete Care Guide (2024)

Japanese Mystery Snail
Japanese Mystery Snail
Dr. Mollie Newton
Published by Dr. Mollie Newton PHD| Senior Editor
Last updated: June 6, 2024
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The Japanese Trapdoor Snail is often described as peaceful, charming, and slimy, which might seem like an unusual appeal, but it fits them perfectly! Similar to their snail counterparts, they flourish in a calm environment, dedicating their time to finding algae and plant material to consume in your aquarium. They play a crucial role in keeping the tank clean.

Article Summary

  • Japanese Trapdoor Snails have a lifespan of 1 to 5 years, and in some cases, up to 10 years; these snails grow to a maximum size of about 2 inches and can grow slightly larger under certain conditions.
  • Their diet primarily consists of algae, but they can also eat fish flakes, fresh vegetables, live plants, and other foods.
  • Japanese Trapdoor Snails are suitable for community tanks but should be kept in a tank with at least 10 gallons of space.

For those new to the aquarium game, snails can often seem like last-minute considerations, but don’t let their small size and solitary nature keep you from including them.

Follow along with me as we look into just what it is that makes Japanese Trapdoor Snails such a worthwhile consideration when looking at new members for your community tank…

Facts About The Japanese Trapdoor Snail

Bellamya chinensis
Bellamya chinensis(1)

Japanese trapdoor snails can be found marketed under several different names, including chinese mystery snails or plain old trapdoor snail.

The mystery snail’s scientific name is Viviparus malleattus, and it can be found in aquariums worldwide but their natural habitat is in the soft and sandy substrate of Japan.


Under ideal circumstances, the japanese trapdoor snail will live between 1 and 5 years, but can reach up to 10 in some cases!

The two keys to keeping japanese trapdoor snails alive for this long are maintaining adequate quality in water parameters and diet.


Trapdoor snails can vary in appearance, but generally range from black to dark green to light brown in color with whorls following along the natural spiral of the shell.

Trapdoor snail shell texture is typically smooth in appearance, but may have a groove along the snail’s growth lines as it grows over time.

The “trapdoor” of japanese trapdoor snails refers to the operculum, which is a small bit of hardened material that covers the opening of the shell when it retracts itself inside.


Japanese trapdoor snails are one of the few fully aquatic snails out there, with no siphon with which to breathe air!

When it comes to males and females it can be difficult to differentiate, but in general female japanese trapdoor snails will have longer antennae, with those of males having an unexplained tendency to lean towards the right.


Japanese trapdoor snails are one of the largest freshwater snails out there, reaching a maximum of around 2 inches. Under certain circumstances, adult trapdoor snails may grow slightly larger depending on diet and care.

Typical Behavior

As with most other snails, japanese trapdoor snails are easy-going creatures who more often than not would prefer to roam around your tank, picking up bits of food and not concerning themselves with others.

These japanese trapdoor snails make such great neighbors because they will typically never have reason to interact with their tank mates, aside from slowly scooting around them if they find them to be an obstacle in their search for food.


It is not uncommon to see japanese trapdoor snails become much more active at night, as many aquarium owners have noticed.


Keep an eye on the lid of your snail tanks as well, because every now and again they may make a dash for the top of the tank and can easily find their way out if not protected.

Food & Diet


Japanese trapdoor snails are not typically picky eaters, preferring to scour the surface of your fish tank for bits of naturally occurring algae.

They can be quite the voracious little algae eaters as well, and attention should be paid to the amount available for each snail in the tank.

If your freshwater fish aren’t eating all of the fish food in the tank, these hungry snails can be found enjoying fish flakes over their normal algae.

Don’t be afraid to experiment to see what your pet enjoys most, some recommend feeding your aquarium snails fresh vegetables, bits of live plants, and bottom feeder tablets.

Our best suggestion is to start small with new foods, offering a bit at a time and removing uneaten food after an hour or so. Even frozen foods in small amounts can be a good option for the japanese trapdoor snail!


A typical japanese trapdoor snail is not a picky eater, and one that is avoiding food should be monitored for illness.

How Do They Fit Into Your Aquarium?

Given their small size and gentle nature, it should come as no surprise that japanese trapdoor snails require little space to themselves in the community tank. As a general rule, a minimum of a 10-gallon tank is recommended for around 5-6 snails.

Keep in mind that these little critters produce their own waste in addition to that of the fish and overcrowding can lead to serious health issues for everyone, such as toxic shock from ammonia buildup.

Don’t be afraid to consider a larger tank if things seem crowded.


While it doesn’t take much room to keep japanese trapdoor snails happy, plan around the largest and most abundant fish in your aquarium.

Japanese Trapdoor Snail Care

While caring for japanese trapdoor snails can be easy and fun when set up properly, it does require some forethought and a bit of planning. These pond snails don’t have a huge list of demands, but can be a vital part of your aquarium hobby.

Here’s a video of a trapdoor snail in an aquarium setting.

Mystery (Trap Door) Snail Climbing

Tank Size

As previously mentioned, a minimum of 10 gallons in your tank should work for several japanese trapdoor snails, but don’t be afraid of going larger!

Trapdoor snails make an excellent addition to an outdoor pond, and can be used to help curb algae growth, especially if your pond has lots of hair algae.

Water Parameters for Japanese Trapdoor Snails

As hardy aquatic snails, japanese trapdoor snails live and thrive in a variety of water parameters. As a general rule they prefer between 65-85 degrees fahrenheit and 6.5-8 pH. Try to keep water between soft and medium when considering hardness.

Test your water parameters often! The best way to prevent your japanese trapdoor snails from getting sick or dying as soon as they’re introduced is to know that they’re headed into a safe environment.


Test your water parameters often! The best way to prevent your japanese trapdoor snails from getting sick or dying as soon as they’re introduced is to know that they’re headed into a safe environment.

How To Set Up A Habitat for Japanese Trapdoor Snails

Aquarium Decoration
Aquarium Decoration

The best place to start with freshwater aquariums for japanese trapdoor snails is with a nice muddy substrate. This will ensure that they’ve got a good base to start with, followed by adding in some live plants and rocks.

The more surfaces for algae to grow on, the better for your japanese trapdoor snails! Adding rocks and decorations with lots of surface area means more food for your snails to munch on.

Breeding Habits

Unlike some other snails which may need a separate breeding tank, as long as you’ve got both male and female japanese trapdoor snails in the same tank, they can produce baby snails.

Thankfully japanese trapdoor snails also don’t reproduce too quickly, breeding once every two years in the wild and every few weeks in captivity.

Each brood typically consists of between 5 and 20 live offspring, which will then be capable of breeding at 18 months of age.

Japanese trapdoor snail reproduction occurs inside of the female, and as such they don’t lay hard eggs but rather produce live young.

Possible Tank Mates

While the japanese trapdoor snail is easy-going and can make good tank mates to most any aquarium fish or snail, certain species (except the Clea helena) are especially good considerations depending on the goal of your tank.


Japanese trapdoor snails make great buddies with others of their own kind! Keep in mind the amount of food available for each and they’ll be a happy snail family.

Good Mates to Consider for Japanese Trapdoor Snails:

Common Care Problems

While diseases amongst japanese trapdoor snails are not common, it is important to know that they can still get sick.

Seeing a japanese trapdoor snail that is not moving, or with an off shell color may be alarming at first, but can often be little cause for concern.

A motionless japanese trapdoor snail is more often than not simply resting in place.


If you notice that after a while the snail is still sitting, give it a gentle poke. If it continues lying in place, it may need to be removed. Dead Japanese trapdoor snails will likely float to the surface and produce a truly nasty smell.


In older snails, oedema can lead to a swelling of the tissues, causing your once-healthy japanese trapdoor snails to look inflamed or puffy. If this happens, there is unfortunately little that one can do aside from removing the affected.


Keep japanese trapdoor snails infected with any form of disease or illness away from others in the fish tank as soon as possible until it subsides or the snail has passed.


Are Japanese trapdoor snails invasive?

In certain areas and countries, Japanese trapdoor snails are considered invasive. Be sure to check with your local guidelines before purchasing!

Do Japanese trapdoor snails eat living plants?

In most instances they will leave your live plants alone when properly fed, but this is not to say that a desperate trapdoor snail won’t!.

Do Japanese trapdoor snails get along with goldfish?

Japanese trapdoor snails make a great tank mate for goldfish! While the goldfish is considered to be a dirty fish and can produce large amounts of waste, this doesn’t mean that they can’t get along with this peaceful snail.


In conclusion, japanese trapdoor snails can make for a most excellent, easy addition to any aquarists community tanks.

They require little in the way of continued care aside from a good-sized tank to crawl around on and enjoy your algae, and will in fact make your cleanup that much easier with their presence!

Feel Free To Share!

We hope that you’ve enjoyed today’s article on Japanese trapdoor snail care, and that it has answered any of your long-unanswered queries.

If you found this information useful, feel free to pass it along to any other fans of this delightful little snail species, and I wish you luck on your aquarium journey!


Featured Image – Gallagher, J. (2017, January 21). Japanese Mystery Snail [Photo]. Wikimedia Commons. https://upload.wikimedia.org/wikipedia/commons/e/e5/Japanese_Mystery_Snail_-_Cipangopaludina_japonica%2C_Leesylvania_State_Park%2C_Woodbridge%2C_Virginia.jpg
1. Oregon Department of Fish & Wildlife. (2010, October 23). Bellamya chinensis [Photo]. Wikimedia Commons. https://commons.wikimedia.org/wiki/File:Bellamya_chinensis.jpg#/media/File:Bellamya_chinensis.jpg

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