How to remove calcium build-up from faucets. Fill baggie with 1 part CLR, 1 part water. Secure filled baggie to the faucet spout with a rubber band and let it for a few hours. Remove baggie and rub off the build up. Use a Magic Eraser if needed.
It worked well, but I had to scrub the remaining residue off the tub with a brush and straight vinegar. ( The water is really hard where we live and I soak my kids dirty clothes often. Cleaning with vinegar was amazing.