Coco Worm (Protula bispiralis)

The Coco Worm (Protula bispiralis) is a hard tube feather duster that builds a solid, calcareous white tube and unfurls a double spiral crown of feathery pink and white radioles from the end of it. Touch the water near it and the whole crown snaps back into the tube in a blink, then slowly blooms open again. This one is a pink crowned specimen. It is completely peaceful and reef safe, and it adds a moving, flower-like focal point to rockwork that no coral quite matches. Browse the rest of our invertebrates and our saltwater livestock and supplies.

Be honest with yourself about one thing before you buy: a coco worm is a pure filter feeder. It has no symbiotic algae and gets nothing from your lights, so it lives on the fine particles in your water. In a young or very clean tank it slowly starves. In a mature reef where you feed phytoplankton and fine foods, it can live for years.

Care Guide

• Mature tank: six months or more with plenty of live rock. Established systems carry the natural plankton and bacteria that a filter feeder depends on.
• Tank size: 30 gallons or larger. Bigger, older systems are more forgiving.
• Feeding: this is the whole game. Dose live or concentrated phytoplankton and fine particulate foods such as rotifers, oyster eggs, or copepods several times a week. For best results, shut off pumps for 15 to 20 minutes and gently puff food toward the open crown with a feeder.
• Flow: moderate and indirect, enough to carry food past the crown without bending it over or blasting it closed.
• Placement: wedge the tube into a rock crevice or lean it into rubble with the crown pointing up and out. Do not bury the base deep in fine sand, where it can suffocate.
• Lighting: not needed. Place it wherever flow and access suit it, including shaded overhangs.
• Water: 74 to 80°F, salinity 1.023 to 1.026, pH 8.1 to 8.4, zero copper. Drip acclimate slowly and keep the tube submerged when you move it.
• Crown loss: a stressed coco worm may drop its crown after a move or a parameter swing. Leave the tube in place and keep feeding; a healthy worm usually regrows a new crown in a few weeks.

Specifications

Compatibility

A coco worm bothers nothing. It fits right in with corals, clams, clownfish, gobies, and cleanup crew, and it pairs naturally with other filter feeders that enjoy the same phytoplankton feedings, like the soft tube Feather Duster and the Ultra Grade Maxima Clam. The risk runs the other way: butterflyfish, most angelfish including some dwarf angels, puffers, triggers, and some larger wrasses and hawkfish will pick at the crown until the worm stops opening. Large hermit crabs and arrow crabs may pester it too. Keep it where corals cannot grow over the tube opening.

Recommended Foods & Supplies

• Reef Nutrition Phyto-Feast Live, a staple phytoplankton for filter feeders
• Reef Nutrition Oyster-Feast, a fine particle food sized for tube worms
• BRS Freeze-Dried Rotifers, a tiny zooplankton food to rotate in
• Bulldawg Reef Juice Elite, an 8-species live phytoplankton blend
• Aquatop Fish and Coral Feeder to puff food right at the crown

FAQ

How often do I need to feed it?
Several times a week. Phytoplankton on most days plus a fine particulate food a few times a week is a good rhythm. A coco worm that stays open and fully extended is eating well.

The crown fell off. Is it dead?
Not necessarily. Coco worms shed their crowns under stress and can regrow them. Leave the tube alone, keep water stable, and keep feeding. If the tube starts to smell or the worm body comes out, it has died.

Does it need strong lighting?
No. It is not photosynthetic at all. You can place it low in the tank or under an overhang where flow brings food past it.

What is the difference between a coco worm and a regular feather duster?
Coco worms build a hard, stony tube and grow a double spiral crown. Common feather dusters build a soft, papery tube. Both are filter feeders with the same feeding needs.

Why does it close every time I walk by?
The crown has light-sensitive eyespots and snaps shut at shadows and movement. That quick reaction is a sign of a healthy worm, and it relaxes as it gets used to the tank.