I was adviced by the pet store to add tap water which I did. Added the Prime treatment, live sand, sea salt and ran a Rena canister filter also a heater. Is there anything I can do to fix adding tap water?
I wouldn't concider it a mistake. It is a common misconception among newer reefers. A saltwater tank will work with tap water, but once you get into corals it is best to use Reverse Osmosis and Deionized water. To correct your problem, I would concider buying a RO/DI (reverse osmosis/deionizer) unit. Or you can buy RO/DI water at your LFS or wal-mart. However, it is more feasible to purchase a unit.