I have a purple/orange lobster, after I dropped him in I think he was under a rock before he hit the bottom. That was a year ago, and I have only seen him once since, late at night after the lights were out and I was looking with a flashlight. I am also thinking that he might be to blame for the disappearance of my favorite mandarin fish. I'm actually thinking of removing him, I would rather have an animal I can enjoy and see contributing to the bio-load.