Mushroom question

[Hitachi]

So I have a little purple/blue mushroom a friend of mine gave me about a month ago, along with some polyps, some pink mushrooms, and a frogspawn. The little mushroom disappeared for a few weeks until I found him under a rock. So, I broke the rock and set it in a place with better light. Now the mushroom appears to crawl in and out of the rock. It peaks out in blue light, and most of the time is all the way out in blue and white, but completely disappears at night and the beginning and end of the blue cycle. Any one ever experience a mushroom behaving this way? Possible reasons?

 

[Alchameth]

My mushrooms shrink down to near invisible at night and they are on frag plugs still. Since they can let go and move, I'd say it's fine and happy where it is and just doing what they do.