It’s good to know that a Berkey water filter doesn’t completely remove calcium from the water. Larger amounts are reduced, and synthetic calcium is removed. However, a Berkey water filter retains beneficial minerals (those that occur naturally in water and are good for human health) in the water. And calcium is one of them. So you retain the mineral calcium in the water, and this can still cause some scaling. In short, a Berkey water filter is not designed to remove calcium from the water.