Berghia nudibranch (Berghia stephanieae) care guide

Group
Other invertebrates
Other names
Aeolidiella stephanieae, Berghia verrucicornis (misapplied), Aiptasia-eating nudibranch, Berghia sea slug
Family
Aeolidiidae
Origin
Florida Keys, USA; shallow water about 1–2 m
Water
saltwater
Maximum size
3 cm
Temperature
22–26°C
pH
8.1–8.4
Hardness
dKH 8–12, SG 1.023–1.025
Minimum tank
40 litres
Care level
intermediate
Temperament
peaceful
Reef safe
yes

Care

Berghia stephanieae is a small, see-through aeolid sea slug covered in finger-like cerata, used by reef keepers to control Aiptasia (glass anemones). It eats nothing but Aiptasia. Adults are about 1–3 cm; sources disagree on the maximum. It was described from the Florida Keys in 2005; before that, aquarium Berghia were usually sold as Berghia verrucicornis, a name now known to have been misapplied, and it was later placed for a time in Aeolidiella. How it works: Berghia hunt Aiptasia at night and are among the best predators of them. Aiptasia sting fish, invertebrates and nearby corals and spread fast, so Berghia are a safe biological control. Add several (often 5–10 for a typical reef tank) at night, away from pump intakes, and expect results over weeks rather than days. Tank set-up: guard pump, powerhead and overflow intakes with foam or mesh, as Berghia are easily sucked in. Avoid predators (see compatibility). Keep the tank stable at reef conditions; the slugs reach maturity in about 60 days at 22 °C. Starving: once all the Aiptasia are gone, the Berghia will starve. Pass them on to another reefer or a shop, or keep a small Aiptasia culture in a separate tank to feed them. Water: about 22–26 °C, pH 8.1–8.4, dKH 8–12 and specific gravity 1.023–1.025. Copper: copper-based medicines are toxic to shrimp, snails and most invertebrates, and some plant fertilisers carry copper too. Never treat a display tank holding this animal with copper; treat fish in a separate hospital tank, and drip-acclimatise new arrivals slowly. Sources: Wikipedia (en.wikipedia.org/wiki/Berghiastephanieae). Checked October 2026.

Diet

Aiptasia anemones only. Juveniles start feeding about 48 hours after metamorphosis. It will not eat corals, other anemones or prepared foods.

Breeding

Hermaphrodite: any two adults can mate. They lay coiled egg masses on rock and glass; early masses hold 60–80 embryos and mature ones 1,000–2,000. The young feed on yolk inside the egg, hatch as veliger larvae shortly before they are ready to settle, and settle and change shape within about a day, so they can grow up in the same tank. Breeding is easy given a steady supply of Aiptasia, and it is bred commercially.

Compatibility and tank mates

Completely reef safe; it harms nothing but Aiptasia. Eaten by many wrasses, peppermint and other Lysmata shrimp, hermit crabs, some crabs, filefish, butterflyfish and dragonets, so it works best in tanks without these. Pumps and overflows are a major danger.

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

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