Wedge sea hare (Dolabella auricularia) care guide

Group
Other invertebrates
Other names
Sea hare, Shaggy sea hare
Family
Aplysiidae
Origin
Indian Ocean and western Pacific including the Philippines; sheltered seagrass, sand, mud and rock pools
Water
saltwater
Maximum size
40 cm
Care level
intermediate
Reef safe
with_caution

Care

The wedge sea hare is a large sea slug that can reach about 40 cm, with a flattened disc at the rear, a short blunt head and a body covered in bumps and skin flaps that give it a knobbly look. It has a small, ear-shaped internal shell. It is the sea hare most often sold to control hair algae in reef tanks. In the wild it lives in sheltered places without strong currents, in seagrass, on sand and mud and in rock pools. In the aquarium it needs a mature tank with plenty of algae and normal reef conditions, with pump and overflow intakes covered, as sea hares are easily sucked in and killed. Our sources give no water figures for this species. Clean-up role: it eats large amounts of hair algae and other green algae and can clear an outbreak quickly. Afterwards it often starves because there is no algae left; plan to rehome it or feed dried seaweed (nori), which some accept. Toxins: when disturbed it squirts a cloud of purple ink. In small tanks, large amounts of ink can stress fish; run activated carbon and do water changes if it inks. A dead sea hare fouls the water fast, so remove it promptly. Copper: copper-based medicines and some plant fertilisers are toxic to shrimp, snails and most other invertebrates. Never dose them in a tank holding this animal, and check the label of any treatment or fertiliser before use. Sources: Wikipedia (en.wikipedia.org/wiki/Dolabellaauricularia). Checked October 2026.

Diet

Herbivore: hair algae, other filamentous and green algae. Once algae is gone, offer dried seaweed (nori) clipped to the rock; many still starve, so it is best used to clear algae and then rehomed.

Breeding

Sea hares are simultaneous hermaphrodites. This species lays long, twisted strands of eggs, usually green but sometimes reddish or yellowish, which are collected and eaten in the Philippines. The larvae are planktonic and it is not bred in home aquaria.

Compatibility and tank mates

Reef safe with caution: it does not eat corals or harm fish, but it can be sucked into pumps and overflows, and its ink can stress tankmates. Its large size can knock over loose frags. Fish that pick at slugs (some angelfish, puffers) may harass it.

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

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