Common Name: The Columbian apple snail, Giant Tropical Ramshorn.

Scientific Name: Marisa cornuarietis

Family: Ampullariidae.

Origin: Brazil, Columbia, Venezuela, Panama, Costa Rica and Honduras. Now introduced into Cuba, Puerto Rico, Florida and Texas.

Maximum Size: 3" in shell height apparently, but 2” would be a good size. Growth is quite slow.

Minimum Tank Size: Should be kept in tanks about 8UK Gals for a group of 4 adults and a few young.

Life Span: Temperature dependent. At a higher temperatures they live shorter, but grow, reproduce and move faster. The opposite is true at lower temperatures. The temperature should not drop below 12 degrees C.

Care: Very easy to care for. Hardy and adaptable, they have both gills and lungs to survive in any Oxygen concentration. They eat any food offered, but a balance of flake foods, sinking pellets, live plants and bloodworm keep them happy. Water can be fast flowing and they do seem to enjoy the fast currents, but slow areas need to be added for a rest.


Preferred Temperature: 22-26 degrees Celsius.


Preferred pH: 7-8, any less than 7 and their shells will corrode.

Feeding: Best all round feed is sinking pellets for catfish. Algae wafers, flakes, catfish tablets and any other sinking food suites Columbians fine. Mine are living happily on a main diet of sinking pellets from an Angling and Tackle shop. The pellets are cheap but seem to do the snails very well. They also love some plants if they are growing too large in another tank. Vallis is loved by them as well as any soft plant, aquatic or not. Vegetables are also enjoyed. They seem to really enjoy meaty foods, so add some bloodworm and prawn pieces.

Breeding: They have totally separate sexes. The male’s penis sheath can also be seen in larger snails. To sex the snail, take the snail out of the water and hold it upside down. I tend to place them in a tub with one cm of water in the bottom. Prop the snail up in one corner. After up to ten minutes, the snail will begin to try to right itself. At this point, make sure the snail can just touch the side of the tub so they think something is there. They will try to come fully out of their shells to right themselves, just keep moving them slightly further away so they can still touch the tub. Eventually, they come fully out and now lift them up. The snail should be trying to grab onto something to right itself and if you look right behind the head, you should see a large, white bulge that some snails have, and others don’t. Snails with the penis sheath are clearly males. Alternatively, watch them mate. The male will be the one on top and his penis will be visible. Although this is a good way of finding a male, the males will also mount other males so what you think is a female may not be at all. The male will try to mate with another (not always female or the same species) snail usually daily if there is enough food to fuel him and the water quality is acceptable. Columbians seem not to really mind who their partner is, other snails are fine. Females lay eggs every 7 days or thereabouts, laying about 3 clutches then having a rest for a few weeks. Columbians become sexually mature at only 1” shell length. I have never bred mine, due to having only had males. They lay underwater eggs like Asolene sp. in small clutches of a couple of dozen eggs.

Notes: Attractive under a red enhancing beauty light. There are golden varieties on sale as well. Their colours do vary slightly, the browns of the shell vary in shade and the stripes vary in thickness.
Columbians do not seem prone to floating like other snails do.

A standard colour male:






This is a Gold male with some shell withering: