Since your urchin is carrying things around, I'm guessing it is Mespilia globulus (image: )?http://www.aquariumarts.com/shortspineurchin.jpeg
This urchin is a excellent herbivore altough it will eat some of your coralline algae. This has been shown to actually accelerate coralline algae growth so you shouldn't have any problems with it. As always with urchins, try not to touch the spines with your bare hands. It does *not* eat detritus so it should be kept in main aquarium where there is some algae growth.
Since your mushrooms came with small rocks it should be quite easy to secure them in place. You can use either super glue or some two part underwater epoxies like "Aqua Medic Reef Construct" or "Salifert Coral Stick". You can use all these products underwater, no need to remove rocks from aquarium.
[ December 09, 2001: Message edited by: tatuvaaj ]</p>
This urchin is a excellent herbivore altough it will eat some of your coralline algae. This has been shown to actually accelerate coralline algae growth so you shouldn't have any problems with it. As always with urchins, try not to touch the spines with your bare hands. It does *not* eat detritus so it should be kept in main aquarium where there is some algae growth.
Since your mushrooms came with small rocks it should be quite easy to secure them in place. You can use either super glue or some two part underwater epoxies like "Aqua Medic Reef Construct" or "Salifert Coral Stick". You can use all these products underwater, no need to remove rocks from aquarium.
[ December 09, 2001: Message edited by: tatuvaaj ]</p>