White dots on rocks

[roundman]

Got this am and with the moon lights on the rocks had these 1/8" white dots all over them. Got out the flashlight and I am the proud papa of 30-50 Nassirus snails. When the room lightened up they were gone and hope they will be back tonight. Very cool.

 

[cameron]

I find when these spawn they create a huge milky white substance all over the tank and causes my skimmer to go nuts. Awesome when it happens but sucks getting my skimmer to keep from overflowing.