Although their appearance can be perplexing, Polychaeta are essential in a SBMarine tank. They are found everywhere even though we rarely see them. Yet they are tireless workers. The category of polychaeta of interest to us are détrituvore and generally grow to 10 / 15cm. There are also larger polychaeta in the wild: most are very venomous, but good quarantine habits isolate these specimens before they reach your tanks.
The specimen in the photos below lodges at the foot of a 5 inch Rhodactis Anemone. This anemone is fed by hand every 48 hours and the polychaeta perfectly knows the schedule. It therefore expects a prize meal every time. This specimen measures approximately 1 inch.
Polychaeta are red-blooded marine worms and therefore can be brightly colored. They tend to become grayish when food resources are deficient. They are opportunistic feeders when an occasion arises and will enjoy the menu offered to other specimens. The most common species in the aquarium trade has a two tone body color: purple and red /orange ... They are a choice food for a wide variety of fish and crustaceans. A marine tank without them is missing something really important and usefull.
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