Hi, I am new on this site. I want to build myself a Koipond. I need help with, the following: How can I treat the pond's water, as I live in the Northern Cape and only have water supplied out of a borehole available. The water is very hard and my plan is to build a window into the pond. I am worried that the hardness of the water will make the window white after a while. Can anybody please assist me with this?