I have a 4 gallon pico reef with mainly hardy soft corals and I'm wondering if I can make salt water out of Manhattan tap water? Reason I ask is that a gallon of distilled water costs about $3 around me and doing a 30% water change every week is getting expense/time consuming. Was wondering if I can just use dechlorinated tap water and have the Caulpera in my tank absorb any heavy metals?