I am new to the hobby. I have a 300 gal system, 4 side viewing. It has been up and running for 3 months and I have started adding fish, corral and invertebrates. Everything looks wonderful. I have a black long spined sea urchin with blue dots and white markings. Can anyone give me more info on this guy. He is amazing to watch. He moves alot and leans against my giant blue clam and an anemone.