Hello; I am new but learning fast, just got an urchin it looks like a blue tuxido but it is more of a purple color. my question is he is doing fine but from the first 2 minutes I put him in the tank he finds little rocks and shells and puts them on his head [or what would be his head on top] and this stuff stays there. Is it ok to just let him dress up in this stuff or should I be pulling it off of him? as quick as I pull it off he finds something else to put on. I haven't had the opertunity to see him get it up there, but I am curious how he does it. I will look away for a minute or two and he will have something else up there. He is pretty cool though.