Knobby Sea Rod

Eunicea sp.

Also known as Knobby Gorgonian, Sea Rod

SaltwaterCoral

Knobby Sea Rod (Eunicea sp.) — Liné1 · CC BY-SA 3.0

Care at a glance

Temperature: 73–81°F (23–27°C)
pH: 8.1–8.4
Adult size: 17.7 in (45 cm)
Minimum tank: 26 gal (100 L)
Temperament: Peaceful
Social behavior: Solitary
Swim level: Bottom
Difficulty: Easy
Breeding: Medium
Rarity: Common
Reef safe: Reef safe
Origin: Caribbean and tropical western Atlantic, including South Florida and Panama
Family: Plexauridae

Overview

Epoxy the base to rock in bright light with moderate to strong flow and it is one of the more forgiving gorgonians available, a good match for the same tanks that suit sea plumes. It photosynthesizes, so feeding is optional, though the big polyps will take fine plankton foods when offered. Growth is upright and steady, so leave headroom and a little space from neighbors, which it will never sting.

In the wild

Knobby sea rods grow on shallow reefs and hardbottom throughout the Caribbean, where they form upright, candelabra shaped clumps of thick tan to brown branches. Each branch is studded with raised knobs called calyces, and when the large fuzzy polyps extend the whole colony turns a deep chocolate brown. Aquarium stock is cultured in Panama at Bocas Mariculture rather than collected from the reef.

Good to know

Eunicea is a Caribbean genus in the family Plexauridae with many look-alike species, which is why cultured colonies are usually sold at genus level rather than with a species name. The knobs along the branches are the protective cups the polyps withdraw into, and they stay prominent even when the colony is fully retracted. Like the sea plumes and sea blades it grows beside, it carries symbiotic zooxanthellae and earns most of its keep from light.

Did you know

The swaying gorgonian forests that cover South Florida and Caribbean hardbottom are built largely of sea rods like Eunicea, so a cultured colony brings a small piece of that landscape into a reef tank.