Colombian ramshorn snail (Marisa cornuarietis) care guide

Group

Snails

Other names

Giant ramshorn snail, Colombian ramshorn apple snail, Columbian ramshorn, Ramshorn apple snail

Family

Ampullariidae

Origin

Northern South America and southern Central America (Colombia, Venezuela, the Guianas, Brazil, Bolivia, Panama, Costa Rica, Trinidad); invasive in Florida, Texas and elsewhere

Water

freshwater

Maximum size

5 cm

Temperature

21–28°C

pH

7–8

Hardness

8–15 dGH, 4–8 dKH

Minimum tank

60 litres

Care level

beginner

Care

The Colombian ramshorn is an apple snail with a flat, coiled shell that looks like a giant ramshorn. Despite its common names it is not related to true ramshorn snails (family Planorbidae) but belongs to the apple snail family, Ampullariidae. The shell is usually 3.5–5 cm across, pale to dark red-brown and often striped. 'Columbian' is a misspelling: it is named after Colombia, not Columbus. Apple snail caution: this is an apple snail, though not one of the Pomacea species covered by the EU import ban. Check the current rules before buying or selling, never release it, and never put it in a garden pond. It is ranked among the worst alien species in Europe and has become established in Florida, Texas, Idaho hot springs, Cuba and Puerto Rico, probably from aquarium releases. Never release this animal or empty its tank water into drains or waterways. Tank set-up: a tank of 60 litres or more without prized plants, with a tight lid. It has both a gill and a lung, so it copes with low oxygen and comes to the surface to breathe. In the wild it lives in still or slow-moving fresh water with plenty of vegetation. Water: tropical, about 21–28 °C, with neutral to alkaline, fairly hard water to keep its shell strong. Behaviour and role: a busy scavenger that eats almost anything, including algae, detritus, dead fish and other snails' eggs. That makes it a useful clean-up snail in unplanted tanks, but it is not suitable for planted aquariums, because it eats large amounts of plant matter. It has been used to control the snails that carry schistosomiasis and to graze water weeds. Copper: copper-based medicines and some plant fertilisers are toxic to shrimp, snails and most invertebrates. Never dose them in a tank holding this animal, check the label of any treatment or fertiliser, and use a separate hospital tank for fish. Sources: Wikipedia (en.wikipedia.org/wiki/Marisacornuarietis). Checked October 2026.

Diet

Practically omnivorous: aquatic plants, algae, detritus, dead animals and snails' eggs. Feed sinking pellets, algae wafers, blanched vegetables and calcium-rich foods. A well-fed snail eats fewer plants, but it will still damage most planted tanks.

Breeding

Sexes are separate (unlike ramshorn snails), so you need a male and a female. Unlike Pomacea apple snails, it lays its eggs under water in flat, disc-shaped jelly clutches stuck to plants, glass and decor. The young hatch as tiny snails and breeding is easy; numbers can build up if food is plentiful. Remove excess clutches to control numbers and dispose of unwanted snails humanely, never in waterways.

Compatibility and tank mates

Safe with fish, but it destroys most aquarium plants and eats the eggs of other snails. Shrimp are usually safe, though it may eat shrimp eggs or a weak shrimp. Avoid puffers, loaches and large cichlids that eat snails.

Last updated 8 October 2026. Community-edited care guide on Aquatic-Auctions.