Apple Snails in the Aquarium

Golden coloured Pomacea bridgesii.

There are many different apple snails of the family Ampullariidae available to the aquarist with different sizes, shapes and appetites. However there are a few characteristics that unite the species:

They have a lung and a gill. They are able to fill the lung whilst remaining submerged by extending a siphon tube to the water surface. Although for long term survival they need to access to both air and aerated water, this enables them to survive for long periods both exclusively in or out of water.

Golden Pomacea bridgesii
showing siphon just below shell entrance
and also operculum at base of shell

They have a covering to the entrance of the shell made of shell material. This is called the operculum and ensures that the snail can seal itself inside its shell for safety. In the wild snails can go into hibernation in mud during a drought for long periods sealed in their shells.
Unlike the majority of snail species that are hermaphrodite, apple snails have separate sexes (gonochoristic), hence requiring a male and a female to reproduce.

The common apple snail genus found in the UK aquatics trade is Pomacea bridgesii – commonly known as brigs. This snail is mainly found as a bright yellow coloured shell with a cream coloured body although other colours (white, blue, purple, green) are becoming more frequently available mainly through individual enthusiasts. Its natural (or wild) colouring is a striped brown and this is also to be found mainly amongst collectors.

The ivory coloured brig has a white shell and a pale cream body. The blue has the same shell but has a black body that gives the shell a blue appearance. Similarly what is known as a jade snail has a yellow or golden shell and a black body giving a green appearance. So far purple through pink shelled snails have been bred with stripes. The absence of stripes in these snails has been a challenge for enthusiasts for a while. Both dark and cream coloured bodies have been combined with purple and pink shells.

Ivory and Blue Pomacea bridgesii.

Like most snails they have a voracious appetite but will not eat healthy living plants unless starving. This makes them suitable for planted aquaria although correct identification of brown striped or yellow snails is vital if plants are present as other snails have similar colourings and will demolish plant collections rapidly. Suitable food for these snails includes catfish algae tablets (although they do not eat algae itself), tropical and coldwater fish food, green vegetables, and fruit.

Pomacea bridgesii in heavily planted tank.
These snails have inhabited this tank for the over six months and the plants have flourished and remained uneaten.

Brigs can grow shells of up to 5-6cm in diameter and can live for up to 2 years. However shell growth and life span is directly proportional to temperature. A snail kept at say 26°C will get bigger faster than one kept at 23°. However it will not live as long. A calcium supplement is necessary for shell growth and condition especially in a soft water area. Iodine supplements are also recommended.

The female lays her eggs above the water line. In the natural habitat this would ensure that the eggs remain safe from fish. This is also an advantage to the aquarist as the egg clutches can be readily removed if more snails are undesired. The brig eggs are pale pink and must be kept moist (not wet). The baby snails will hatch after about two weeks. It is essential to allow a couple of inches of glass above the water line for the snails to lay eggs. Good water quality is also important. It should be noted that just because two snails are mating, one is not necessarily female. The males of this genus get a mating urge that drives them to attempt to mate with any snail of a similar size!

Another genus of apple snail that is very popular in the aquarium is Pomacea canaliculata or cana. This snail is much bigger than the brig and will grow up to 7cm. It usually has either a striped brown shell with a pale or dark mottled body or a yellow golden shell with a cream body. It can be distinguished from the brig by shell shape and size, egg colour and plant eating!

Brown striped Pomacea canaliculata at water surface.
Note the siphon is un-extended at this time.

The eggs are a dark orange in this genus and again are laid above the water line. The babies of this genus grow at a much quicker rate than the brig young. This snail will devastate any plants in the aquarium and has a much bigger appetite than the brig.

The genus Pomacea haustrum is also encountered in the aquatics trade. This is very similar to the cana although has a slightly different shaped shell, lays bright green eggs and grows up to 12cm. The giant ramshorn snail or Marisa also can be found. Although it has a significantly different shaped shell, it still has an operculum, breathing siphon and the other apple snail characteristics. It lays its eggs below the water surface.

For further information see www.applesnail.net

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