Money Cowrie - Erosaria annulus

Money Cowrie (Erosaria annulus)

The Money Cowrie is an attractive marine snail recognised for its smooth, glossy shell and distinctive golden-yellow ring marking across the upper surface. Peaceful, compact and useful as part of a clean-up crew, it spends much of its time grazing biofilm, microalgae and organic material from live rock and aquarium surfaces. It is generally well suited to established reef aquariums, provided stable water conditions and sufficient natural grazing are available.

Common Name:
Money Cowrie, Gold Ring Cowrie, Ring Cowrie

Scientific Name (Latin):
Erosaria annulus

Maximum Size:
Approximately 5 cm

Water Type:
Marine

Origin / Natural Habitat:
The Money Cowrie has a broad Indo-Pacific distribution and is commonly associated with shallow reef flats, rocky coastal areas and other hard-substrate marine habitats. It is frequently found in shallow water where it grazes across rock surfaces and retreats into crevices for shelter.

Water Parameters:
Temperature: 24–26°C
pH Range: 8.1–8.4
Salinity: SG 1.024–1.026
Nitrate: Low and stable
Copper: Must be avoided

Temperament:
Peaceful

Money Cowries are peaceful marine snails and can generally be kept alongside other suitable reef invertebrates and non-predatory fish.

They do not normally show territorial behaviour and can be maintained singly or in groups where sufficient food and grazing surfaces are available.

Diet:
Algae Grazer / Detritivore

The Money Cowrie naturally grazes biofilm, microalgae and organic material from rock and other hard surfaces.

In the aquarium, a mature supply of natural algae and biofilm is particularly valuable. Supplementary foods can include nori, spirulina-based foods, algae wafers and other suitable herbivore preparations if natural grazing becomes limited.

Minimum Tank Size:
Approximately 60 litres

A mature aquarium with established live rock and sufficient natural grazing surfaces is more important than sheer aquarium volume.

Behaviour & Activity:
The Money Cowrie spends much of its time moving slowly across live rock, glass and other hard surfaces while grazing.

It is often more active during lower-light periods and may retreat beneath rockwork or into crevices during brighter parts of the day.

Its mantle can extend partially or completely over the glossy shell while the animal is active, helping maintain the shell's characteristic polished appearance.

Reef Safe:
Reef Safe

The Money Cowrie is generally considered reef safe and is valued for grazing algae and biofilm without normally damaging healthy corals.

As with most grazing invertebrates, individual behaviour should still be observed, particularly in aquariums where natural food becomes scarce.

Special Requirements or Care Notes:
A mature marine aquarium with established rockwork and natural biofilm is recommended.

Stable salinity and water chemistry are particularly important, and careful acclimation should be used when introducing the cowrie.

Copper-based medications must never be used in an aquarium containing this or other marine snails.

Avoid housing Money Cowries with fish or invertebrates that naturally prey on molluscs, such as some large wrasses, puffers and triggerfish.

Supplementary feeding may be required if the aquarium is extremely clean or natural algae and biofilm become depleted.

Suitable for:
Beginner

Availability:
Regularly available

All images are a visual representation of the invert you will receive, made to be as accurate as possible. Please note that Mother Nature is a wonderful thing, and variation in patterns and colours will occur — that is part of the unique beauty of these animals.