Very awesome creatures, a friend if mine offered me one a few months ago and after thinking aboutbit decided against it. They dont do much until feeding time, they burrow their entire body into the sand or in rock with just the head exposed. If you try to keep any fish with it, they will most certaily be eaten. The bobbit worms feeding habbits remind me of the graboids from tremors. They wait patiently for a meal to bump into them and then the bobbit worm ambushes the prey and quickly drags it under the substrate. Good luck in your search for one, and watch your fingers!
