sea worms: they form hard shelled tubes around their bodys. they have a wide variety of brightly colored worms. they look like chewed gum. 5 types of sea worms the christmas tree worm grows to about 5 inches shaped like a christmas tree. they are found mainly in the caribbean. magnificent feather duster which is the largest duster in the world. they are brown and white. grow to about 4 inches long. the large-eyes feather duster they are found in the atlantic ocean. they grow up to 5 inches. they are orange-red to reddish-brown. they are usually found in maine. orange fireworm can grow to about 6 inches. they are found under rocks and coral. red-rim flatworm can grow from 1 to 2 inches they can be any color you can think of.