Description
Frilly Sea Slug (Elysia crispata)
Overview
The Frilly Sea Slug, also known as the Lettuce Nudibranch or Lettuce Sea Slug, is a stunning and vibrant marine invertebrate famous for its ruffled, lettuce-like body. Available in shades of green, yellow, and blue, it adds a splash of color and movement to any peaceful reef aquarium.
Origin
Native to the Caribbean and Western Atlantic, Elysia crispata inhabits shallow coral reefs and seagrass beds, where it grazes on algae and absorbs pigments from its food for coloration.
Feeding
Primarily herbivorous, feeding on filamentous algae such as Bryopsis and Derbesia. It also performs a unique process called kleptoplasty — storing chloroplasts from algae to harness light energy, much like a plant. Provide access to natural algae or supplement with appropriate algal foods.
Tank Mates
Completely reef-safe and peaceful. Best kept with non-aggressive fish, snails, and other gentle invertebrates. Avoid strong water currents and tank mates that may nip at soft-bodied species.
Aggression
Peaceful. Does not bother other tank inhabitants.
Experience Level
Recommended for intermediate aquarists. Requires a mature, algae-rich aquarium with stable parameters and gentle flow. Sensitive to changes in salinity and temperature.
Water Parameters
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Temperature: 74°F – 80°F (23°C – 27°C)
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Salinity: 1.023 – 1.025 SG
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pH: 8.1 – 8.4
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Alkalinity: 8 – 12 dKH
Graceful and captivating, the Frilly Sea Slug (Elysia crispata) is a beautiful and peaceful addition to well-established reef aquariums, combining color, curiosity, and natural algae control.




