I found the sponge in my eheim pump is rock hard. It looks calcified. I was surprised the pump is still running. All of my other equipment seem to be calcified. I recall dosing calcium agreesively and still couldn't keep it up. I found my magnesium was low. Is this caused by low magnesium? I need to adviod this in the future. I have days of cleaning to do. My return pump runs through a chiller and it appears to be slowing down. I wonder if I need to clean inside the chiller. Any way to clean it fast and safe?

