Colombian Giant Ramshorn Snail Care Guide - Setup, Diet & Breeding

The Colombian Giant Ramshorn Snail is a large, striking freshwater snail with a rounded, disc-shaped shell that resembles an oversized ramshorn shell. Its shell may be golden, brown, cream or olive, often with darker spiral bands, while the body ranges from pale beige to dark grey. The shell is coiled sideways rather than forming the tall spire seen in many other aquarium snails.

These snails are active grazers and spend much of their time moving across glass, substrate, plants and décor in search of food. They use a broad muscular foot to glide along surfaces and may also rise to the waterline to take atmospheric air through their siphon-like breathing tube.

Marisa cornuarietis is generally peaceful toward fish and other invertebrates, although its appetite can make it a destructive presence in a planted aquarium. It is capable of consuming soft aquatic vegetation, algae, biofilm and decaying organic matter, and it often becomes most active during the evening and at night.

In the wild, this adaptable snail inhabits quiet or slow-moving freshwater environments such as ponds, marshes, canals and gently flowing streams. Its tolerance and fast reproduction have enabled it to establish itself outside its native range, where it can sometimes affect aquatic plants and local ecosystems.

Despite their common name, Marisa cornuarietis is native to a broad area of tropical and subtropical South America, including Colombia, Venezuela, Brazil, Bolivia and surrounding regions. Populations have also become established in parts of Central America, the Caribbean and the southern United States after introduction.

Allow at least 60 litres for a small group, with a larger aquarium preferred because these snails produce considerable waste and can grow substantially. A tank around 60 × 30 × 30 cm or larger provides useful floor space, and a secure cover is important because they may climb above the waterline. Use smooth sand or fine gravel, sturdy wood and rocks, and leave open surfaces for grazing. Hardy plants such as Anubias and Java fern are more likely to withstand their feeding than delicate stem plants. Stable, moderately hard to hard freshwater around 20–28°C, with a pH of approximately 7.0–8.5 and ample calcium, supports healthy growth.

Adults can reach approximately 7 cm (2.8 in) in shell diameter. Females are often slightly larger and more heavily built than males, although individual size varies with diet, water chemistry and age.

These omnivorous snails graze on algae, biofilm, soft plant growth and decomposing organic material, but they should not rely solely on natural growth in the aquarium. Offer sinking algae wafers, blanched vegetables such as courgette, spinach and cucumber, and occasional protein-rich foods such as shrimp pellets or frozen foods. Calcium-rich foods and mineral supplementation help maintain a strong, well-formed shell. Remove uneaten food promptly to limit overpopulation and water pollution.

Colombian Giant Ramshorn Snails can live with peaceful community fish such as tetras, rasboras, danios, livebearers, small gouramis and peaceful corydoras. They are also generally compatible with calm shrimp, provided the shrimp are not kept with fish that prey on them. Avoid pufferfish, loaches, large aggressive cichlids, crayfish and other snail-eating species, as these may injure or consume them. Their tendency to eat soft plants also makes them a poor choice for delicate planted displays.

Colombian Giant Ramshorn Snails have separate sexes and reproduce readily in suitable aquariums. After mating, the female deposits a gelatinous egg mass on submerged plants, hardscape or the aquarium glass. The eggs hatch after roughly two to three weeks, depending on temperature, and the young snails begin grazing immediately. Provide calcium-rich water and plenty of food if you want the juveniles to develop strong shells.

The sexes are separate, unlike in many smaller aquarium snails. Females are usually somewhat larger and broader-bodied, while males tend to be smaller and slimmer; reliable identification generally requires observing the reproductive organs or mating behaviour.