Pink & White Coco WormHow to Care for Pink & White Coco Worm written by Dave Burr Coco Worms, also knows as Hard Tube Coco Worms, build a calcareous tube which is hard like a shell. The crown can retract within the tube for protection. Coco worm are filter feeders and benefit from feedings of phytoplankton and other liquid foods for filter feeders. Placement: When placing Pink & White Coco Worms in the aquarium you may bury them in the sand with the crown end of the tube