does this harm or kill the corals or just irritate them? i seen them all around some sps. should they be radicated or r they harmless?
some r actually on the skeleton of the corals.
"The animals use the mucous gland in their foot to produce a large of amount of mucus. The mucus is extended up into to the surrounding water by the tentacles on the feet (Hyman, 1967; Kohn, 1983). The strands can extend quite some distance depending on the water flow and the size of the animals. In my aquarium, vermetids about 3 mm (1/8th inch) across can project mucous strands over 60 mm (2.5 inches). I have seen some large vermetids that were over 50 mm (2 inches) in diameter on reef flats in Palau. The strands of mucus from these animals extended over 2 m (about 6.5 feet).
Mucus is sticky, and planktonic materials adhere to it. After a short time the animal "reels in" the strand with its catch stuck to it and eats it. Some species have been documented to feed together. When one individual starts to put out mucus, all of its neighbors do too, producing a mucus sheet that seems especially good at collecting plankton. Once one individual starts to withdraw the strand, all of the contributors do as well, and all get to share in the catch (Hyman, 1967). This ciliary-mucous suspension-feeding isn't the vermetids’ only feeding mode, though. They also have been documented to extend from the tube and catch small planktonic animals, and they seem especially responsive to crustaceans (Hyman 1967). In aquaria, they are probably quite able to feed on baby brine shrimp, as well as other small planktonic animals."
R.L. Shimek
