Decorator Arrow Crab – Detailed Guide: Care, Diet and Facts

The decorator arrow crab is known for its distinguished decorative appearance and behavior. They like to attach things like coral, rocks, and algae to decorate themselves, making them one of the few crab species that like to decorate themselves.

Here you will learn everything you need to know about decorator arrow crab care, diet, tank setup, and facts.

Quick overview of decorator arrow crab

Some facts about the decorator arrow crab (frilly arrow crab)

·        Habitat/Distribution

This crab can be found throughout the shallow reefs, rock and reef caves, wharf piling, and sandy bottoms of the Caribbean and most of the arrow crab species come from the Caribbean while others are imported from the Atlantic, Indo-Pacific region, eastern Africa and California.

·        Camouflage

This crab produces saliva (spit) that works as glue, they attach algae, small rocks, zoas, sponges, corals or something else they like to their body with that. That’s why they look like they decorated themselves, from where they got their name; frilly or decorator arrow crab.

They do this to blend themselves with their surroundings so that predators don’t easily find them, not to decorate the body.

·        Appearance

This crab can sometimes be confusing because of their leg appearance and spideresque movements making them look like a cross between spider crab and arrow crab.

• Some aquarists noticed that this crab molts a lot.
• The females of decorator arrow crabs are smaller than the males.
• You should be cautious with their behavior because they can become aggressive and territorial with their own species meaning you can keep only one crab in a tank.

How to care for decorator arrow crab

This crab is very hardy compared to other crabs and can live up to 5 years. But keeping them alive won’t be easy if you don’t follow the regulations.

Tank setup

Tank size

They will require much space to crawl around meaning a minimum 20-gallon tank is suggested. 25 to 30 gallons with some tank mates.

Substrate

As they live in sand in the wild, they’ll need plenty of sand as substrate, you can use Aragonite sand (it is considered one of the best saltwater substrates) or any other substrate you are comfortable with. If you are using gravel, ensure the grains are small.

Decoration

Decorate the tank with a lot of caves and hiding places, being nocturnal they will hunt at night and sleep or rest the whole day beneath rocks.

You can use some aquarium rocks on the substrate as their main hideout. Then place some zoanthids, anemones, and corals as they will wear them. You have to be accepting of coral damage.

Some live plants will be nice for more hideouts. You can place some plants like halimada, green finger, mermaid’s fan, and Chaeto (Spaghetti Algae).

Temperature and water parameters for decorator arrow crab

The arrow decorator crab will require a temperature between 75 to 78° Fahrenheit or 24 to 26° Celsius. A slight change in temperature will not cause any issues. However, as it plays a crucial role you should use a heater.

The salinity level should be 1.020 to 1.026 with a pH level of 7.7 to 8.4 and dKH 8-12.

Feeding

The decorator arrow crab is a carnivore crab (usually crabs are omnivores) but they can eat fish waste and particles of food too. They can hunt and control the population of small worms like fire worms and flatworms as well as small crustaceans. They can also feed on debris and prey on feather dusters and some corals or pests removing directly from corals. Any kind of meaty food and fish food can be a good option.

You can supplement their food with flakes or palates. However, experts suggest giving them marine meaty food like chopped squid. To prevent aggression or disturbing corals you have to ensure they get enough food.

Decorator arrow crab tank mates

You can’t choose another decorator arrow crab as a tank mate as they become territorial with the same species but they can cooperate with other fish, crustaceans, corals, and snails. Here is a list of tank mates.

List of fish, Crustacean & other

1. Clownfish
2. Snails
3. Blue leg hermit crab
4. Red tip hermit crab
5. Polka dot hermit crab
6. Bubble tip anemones
7. Emerald crab
8. Giraffe serpent starfish
9. peppermint shrimp
10. Pajama cardinalfish
11. Tailspot blenny
12. Orange encrusting montipora
13. Highlighter branching frogspawn
14. Pink tip frogspawn
15. Clove polyps
16. Pulsing xenia
17. Green branching hammer
18. Nexus burst bubble tip anemone
19. Orange frogspawn razzle
20. Watermelon bubble tip anemone
21. Highlighter bubble tip anemone
22. Blue mushroom