I just use soap and water to clean the leaves on my orchids but I don't know if it will help remove calcium build up. If I were you I would try to keep the water off the leaves when you're watering and get a cheap spray bottle from your local hardware and fill it with distilled water. Each time you water your plants, go back with the spray bottle to rinse the leaves with a little distilled water. It's worth a try. Good luck.