In case you want to use a more controlled method of coral placing. I suggest you use the well know bridal veil method. This material can be found in most craft supply stores or fabric stores, and is very cheap.
The other thing you can do is wait for it to detach and slice and dice it into 4 pieces (like a pizza) and set yourself up with 4 new mushrooms. Check out the article on garf on this:
http://garf.org/trever/MUSH.html
By the way, if you choose to cut it the use of supplemental iodine will help the shroom recover.
It might be propagating naturally, however, you'd see the baby shroom before it detaches. I'd say it's just not comfortable, maybe it's overcrowded. But it is perfectly normal for this to happen.
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&&&&20 Gal. , Millenium 1000 & 2000 filter, 130watt Corallife 50/50 reef lamp. Maroon Gold-striped Clown, Pygmy (Cherub) Angel, Skunk Cleaner shrimp, 8 Turbo Snails, 1 unknown cone snail , a branch of red grape calerpa , Sun Polyps, Blue-Green Striped shroom, Red shroom, Zoo Polyp colonies, & Green Star polyps, green monti.
