Japanese Trapdoor Snail - Sinotaia quadrata

Japanese trapdoor snails (Sinotaia quadrata) are a popular choice for aquarium and pond enthusiasts due to their algae-eating habits and unique "trapdoor" shells. They are relatively large freshwater snails, reaching 2-3 inches in size, and are known for their ability to clear uneaten fish food and algae from their environment. They are also known for their hardiness and adaptability to various water conditions. 

Key characteristics of Japanese trapdoor snails:

Unique Shells: They have a spiral-shaped shell with a tough "trapdoor" (operculum) that seals the opening when the snail retracts inside. 

Size: They can grow up to 2-3 inches in diameter. 

Algae Eaters: They are effective algae and uneaten food consumers. 

Hardiness: They can tolerate a wide range of water conditions and temperatures, though they prefer slightly hard water with a pH between 6.5 and 8. 

Calcium Needs: Like other snails, they require a calcium source to maintain their shells. 

Sexing: They can be sexed by observing their antennae; females have two antennae of equal length, while males have one antenna that is shorter (and also serves as a reproductive organ). 

Lifespan: They can live for 5-10 years in a pond. 

Tank and Pond Considerations:

Tank Size: 1-2 snails per 10 gallons of water in an aquarium is a good stocking density. 

Pond Size: 1-2 snails per square foot of pond space is recommended according to Arizona Aquatic Gardens. 

Substrate: They prefer soft substrates like mud or silt, but can adapt to other fine substrates. 

Water Flow: They are often found in slow-moving water. 

Vegetation: They appreciate plants and vegetation in their environment. 

Calcium Supplement: A calcium source is necessary for shell health. 

Acclimation: Gradual acclimation to a new environment is important, similar to acclimating new fish.