MY SNAILS JUST SPAWNED

I went down stairs and noticed my frag tank was really cloudy almost like if i added to much kalk.  I rushed over and looked inside and saw atleast 15 snails spewing out white stuff.  I recorded a 2 min video the link is below.  it was pretty cool my corals liked it all my lps had there feeding tenticles out and my skimmer is going crazy I watched them spawn for atleast 30 min
http://s1228.photobucket.com/albums/ee457/ninjazx777/?action=view¤t=0711112000.mp4

 

click on the first video on the page

 

There spawning again. it must be a all night snail orgy

 

What i find interesting is that i have snails in 4 different tanks that are all connected but there only spawning in one tank and its almost every snail in that one tank