Sea Hare

Care Summary

The California Sea Hare is one of the most effective nuisance algae eliminators in the marine hobby, capable of mowing through large blooms of hair algae, Bryopsis, and green film algae faster than almost anything else you can add to a tank. It does best in larger tanks with ample algae growth and coexists without issue alongside fish, corals, and most invertebrates, making it a great temporary cleanup addition. Be aware that when stressed or threatened, it releases a harmless purple ink and, more critically, a milky secretion that can be toxic to fish in a small, enclosed system, so always acclimate it carefully and have a plan if it needs to be removed. Once it has cleared the algae problem it was brought in to solve, rehome it or supplement its diet with nori and sea lettuce to prevent it from starving in a clean tank.