The only way I got our to hatch was by refilling the water and then I had to break open some of the eggs. Once two babies were free'd manually, the others followed on their own.
I love the ivories! And I have a beautiful purple boy, Little Red, who I would love to get babies out of- he's stunning! Our local pet store is actually dying to get their hands on our babies since they lost their last supplier, and only ever get black ones in stock.
Next on my list is to acquire a golden one! I love all the colors these guys come in!