They are harmless and are a good sign. filter feeders.
SPIRORBIS SPP. Spiral tube feather dusters (spirobids)
-(6mm) 1/4" diameter or larger
-Tropical seas.
-small tanks and larger
-lighting immaterial
-feed on particulate organic material and phytoplankton. Probably survive on dissoved nutrients in many tanks.
-Easy to maintain and are harmless.
-These are the tiniest of the feather dusters and make their way into virtually all marine aquariums. Tubes are usually spirally coiled about 1 1/3 to 1 1/2 whorls and often first spotted on the walls of the tank. The minuscule crown is generally brilliant red or blaze orange, but tentacles are difficult to see because of their small size. Spirorbids are simultaneous, self fertilizing hermaphrodites. The larval period is short and the adults brood the larvae in their tubes. Juveniles exit the parent's tube and crawl a a short distance before starting to secrete their own tubes. once the tube is started they remain in place life. No special care is needed to maintain these harmless animals. eaten by copperband butterflyfish.
ALSO SEE THE HELPFUL ARTICLES ON WORMS.
SPIRORBIS SPP. Spiral tube feather dusters (spirobids)
-(6mm) 1/4" diameter or larger
-Tropical seas.
-small tanks and larger
-lighting immaterial
-feed on particulate organic material and phytoplankton. Probably survive on dissoved nutrients in many tanks.
-Easy to maintain and are harmless.
-These are the tiniest of the feather dusters and make their way into virtually all marine aquariums. Tubes are usually spirally coiled about 1 1/3 to 1 1/2 whorls and often first spotted on the walls of the tank. The minuscule crown is generally brilliant red or blaze orange, but tentacles are difficult to see because of their small size. Spirorbids are simultaneous, self fertilizing hermaphrodites. The larval period is short and the adults brood the larvae in their tubes. Juveniles exit the parent's tube and crawl a a short distance before starting to secrete their own tubes. once the tube is started they remain in place life. No special care is needed to maintain these harmless animals. eaten by copperband butterflyfish.
ALSO SEE THE HELPFUL ARTICLES ON WORMS.