Lepas spp. - Barnacle Cluster

Despite their shell-like plates, Lepas barnacles are crustaceans rather than molluscs. Each animal attaches permanently to a substrate with a flexible stalk called a peduncle. The body is protected by calcareous plates at the end of the stalk.

During feeding, the barnacle opens between the plates and repeatedly extends feather-like cirri into the current. These appendages capture plankton and small suspended organic particles.

The product is sold as Lepas spp., meaning that the animals have been identified to genus level but not necessarily to one exact species. Appearance, stalk length, colony size and the number of individuals therefore vary naturally.

Key features

• Living cluster of Lepas goose barnacles
• Stalked filter-feeding crustaceans
• Not molluscs or ordinary shellfish
• Captures plankton with feather-like cirri
• Permanently attached to a substrate
• Requires continuous water movement
• Requires several small plankton feedings daily
• Accepts phytoplankton and fine zooplankton
• Completely peaceful
• Generally reef safe
• Does not consume corals
• Does not graze algae
• Not a conventional clean-up-crew animal
• Suitable only for established marine aquariums
• Sensitive to sediment accumulation
• Requires strong filtration and nutrient control
• Lighting is not essential for nutrition
• Advanced care level
• Colony size and appearance vary naturally

Care information

• Scientific identification: Lepas spp.
• Family: Lepadidae
• Animal group: stalked barnacle crustaceans
• Diet: plankton and suspended organic particles
• Feeding method: suspension feeder
• Movement: permanently attached
• Temperament: peaceful
• Reef compatibility: generally reef safe
• Care level: difficult
• Flow: continuous moderate-to-strong indirect flow
• Lighting: low to moderate
• Recommended system: established aquarium designed for suspension feeders

Suggested tropical water conditions

• Temperature: approximately 23–27 °C
• Specific gravity: approximately 1.023–1.026
• pH: approximately 8.0–8.4
• Alkalinity: approximately 7–11 dKH
• Calcium: approximately 400–450 mg/l
• Magnesium: approximately 1,250–1,400 mg/l
• Ammonia: 0 mg/l
• Nitrite: 0 mg/l
• Oxygenation: high

Exact temperature requirements may vary because the product is identified only to genus level.

Feeding

Offer a varied combination of:

• Live phytoplankton
• Live zooplankton
• Rotifers
• Copepod nauplii
• Artemia nauplii
• Fine liquid plankton foods
• Finely powdered suspension-feeder foods
• Microalgae preparations

Feed several small portions daily. Introduce the food upstream so the current carries particles through the extended cirri. Avoid forcing concentrated food directly into the animals.

Introduction

1. Confirm that the aquarium is completely established.
2. Check compatibility with fish and crustaceans.
3. Select a sediment-free area with continuous indirect flow.
4. Acclimate the colony slowly to temperature and salinity.
5. Handle only the attachment substrate.
6. Never pull or lift the animals by their stalks.
7. Transfer the colony underwater whenever possible.
8. Secure the substrate firmly.
9. Direct broad water flow past the colony.
10. Monitor the extension of the feeding cirri.
11. Offer a small plankton feeding after the animals open.
12. Monitor nitrate, phosphate and feeding response closely.