I've read conflicting stories on that. anywhere from 3-6 months. The type I have are only interested in encrusting/plating monti's and never touched my digi's at all last time. I hope they don't develop a taste for the branching variety this time. When the green cap is gone I'll more than likely cover it's skeleton with some different types of LPS. The spot below the biggest plate that's left will be perfect for a big elegance or sun coral.