Orange Sea Fan Sponge

Orange Sea Fan Sponge: a bright orange, fan-shaped, non-photosynthetic sponge on a short stalk (likely an axinellid such as Phakellia or Axinella; not a gorgonian). Filter feeds on bacteria, phytoplankton and dissolved organics, so it does best in mature, food-rich tanks with regular phytoplankton and fine particulate feeding. Never expose it to air; trapped air kills sponge tissue. Light: Low; shade limits algae on its surface. Flow: Moderate to strong, indirect. Placement: Shaded bottom rock or under an overhang. Space: About 3 inches. Growth: Slow.