TankBud

Rock flower anemone

Phymanthus crucifer

Also known as Beaded Anemone, Red Beaded Anemone, Flower Anemone, Rock Anemone

SaltwaterAnemone

Rock flower anemone (Phymanthus crucifer)
Nhobgood Nick Hobgood · CC BY-SA 3.0

Care at a glance

Temperature
75–81°F
24–27°C
pH
8.1–8.4
Adult size
3.9 in
10 cm
Minimum tank
20 gal
75 L
Temperament
Peaceful
Social behavior
Solitary
Swim level
Bottom
Diet
Photosynthetic
Difficulty
Medium
Breeding
No record
Rarity
Common
Reef safe
Reef safe with caution
Family
Phymanthidae
Origin
Caribbean Sea and West Indies

Overview

The rock flower anemone is a Caribbean anemone that is better thought of as a reef friendly color anemone than a host. It suits a reef keeper with a little experience.

Did you know

Rock flower anemones are one of the few anemones widely propagated by coral farms rather than collected from the wild. Named morphs like Ultra Red or Ultra Rainbow are traded almost like designer coral frags.

Caring for the rock flower anemone

Give a rock flower anemone a stable perch on the lower to mid rockwork, under moderate to strong lighting. It is one of the few true anemones that stays put, unlike a roaming bubble tip or carpet anemone. Once it picks a spot it typically roots there for good, which makes placement easy. Gentle to moderate flow should carry food to it without battering the disc.

It needs a tank of at least 20 gal (75 L). Keep the water at 75 to 81°F (24 to 27°C) and a pH of 8.1 to 8.4. Add it only once the tank has been stable for a few months, and acclimate it slowly.

It carries symbiotic zooxanthellae like other reef anemones. Target feed it mysis or chopped shrimp now and then for the best color.

It can still sting a coral planted too close, and its tentacles carry a real punch for their size. Give neighboring corals a few inches of clearance, and handle it with gloves. It partners with certain anemone shrimp and porcelain crabs.

It can reproduce by pedal laceration, leaving small clone fragments at its base that grow into new anemones. An established rock flower can slowly multiply on its own.

Good to know

The rock flower anemone, Phymanthus crucifer, belongs to the family Phymanthidae. It shows an unusually wide range of natural color morphs, from sandy tan and green to vivid red, orange and purple.

In the wild

The rock flower anemone is found across the Caribbean and West Indies. It wedges its column into a crevice or buries it in sand between rocks, leaving only the beaded, colorful oral disc showing. Unlike several of its Indo-Pacific relatives, it does not host clownfish.

Symbiotic relationships

Shrimp and crabs that live in anemones

Several small crustaceans live where almost nothing else can: among the tentacles of an anemone. Sexy shrimp perch in the tentacles in a cluster, bobbing their tails in the display that named them. The white-spot anemone shrimp is near transparent apart from its spots and lives on carpet anemones. The porcelain anemone crab sits at the anemone's edge and filters plankton from the water with two fan-like arms. Pederson's cleaner shrimp lives in the Caribbean corkscrew anemone and cleans fish from there. In every case the anemone is a bodyguard: its sting keeps off the small fish that would eat the shrimp. The anemone gains little, and the white-spot shrimp will nibble its host's tentacles when it is hungry.

Give each of them its anemone. Sexy shrimp take a rock flower anemone, a bubble tip or a carpet. The white-spot shrimp and the porcelain crab want a carpet anemone or a long tentacle anemone, both of which need a mature tank at the tank size their profiles list. Pederson's shrimp wants a corkscrew anemone or a condy. Without a host they perch on a coral or hide in the rock and are picked off by any fish that eats shrimp, so they suit a peaceful nano reef. A clownfish will evict them from an anemone it has claimed.

Every symbiotic relationship in the catalog

Common questions

What size tank does a rock flower anemone need?

A rock flower anemone needs at least 20 gal (75 L).

What temperature and pH does a rock flower anemone need?

A rock flower anemone is comfortable at 75–81°F (24–27°C) with a pH of 8.1–8.4.

What does a rock flower anemone eat?

A rock flower anemone carries symbiotic zooxanthellae, like other reef anemones. Target feeding of mysis or chopped shrimp now and then brings out its best color.

How big does a rock flower anemone get?

An adult rock flower anemone reaches about 3.9 in (10 cm).

How does a rock flower anemone breed?

A rock flower anemone can reproduce by pedal laceration. It leaves small clone fragments at its base that grow into new anemones, so an established one slowly multiplies on its own.

Related species