As Fred's Hens said, it sounds more like she has an absorbtion problem. It kindof sounds like she get all the calcium she could possibly need. Maybe you could try adding magnesium and vitamin D and B to her diet to help her absorb the calcium she is already getting rather than adding even more calcium (which in growing mammals could lead to hyper calcification, dunno if it is the same for chickens).
As far as the liquid calcium suplement, I use a coral calcium (because it has other trace essential nutrients, and is very bioavailable [ie-readily accepted by the body]) that is actually designed for people. The dosing is two tablespoons per day for an adult human. I use 1/8 teaspoon when I give it to my hens, usually only once or twice a week, but more often, I just use plain yogurt. I use the human calcium suplement when I happen to be out of yogurt.
