Brown Feather Duster (Sabellastarte sp.)

This tubeworm spends its whole life anchored in a self-built parchment tube, fanning a spiral crown of feathery radioles out into the current to catch passing plankton and detritus — and yanking the whole thing back inside instantly at the first sign of a shadow or touch. It's a completely stationary animal, so placement matters: pick a spot with steady flow and just enough light, and it'll sit there filtering for years without needing to move an inch.

Care level: Easy · Light: Low-moderate · Flow: Moderate · Placement: Rockwork, out of direct high flow · Diet: Filter feeder, phytoplankton/suspended particulates