too high of a calcium level?

Question
We recently purchased a new 125 gallon tank for our saltwater reef.  Though we have had no problem with it before our calcium level in the new tank is 512.  We are not sure how to lower the level without adding more hard coral or invertebrates.  We tried mixing two new batches of water and used a different brand of salt with each one but when we tested it, the calcium was high in those as well.  Any suggestions  would be greatly appreciated.  Thank You
                Jennie

Answer
Hi Jennie,
Welcome to marine aquatics! Test your source water. Thats probably the culprit. 512 is high but not dangerous. It can lower alkalinity and raise pH, but those are more easily maintained. If pH and DkH are in line then you really dont have much to worry with. Mine personally doesnt get below 600 where I live and my corals and inhabitants do just fine. I just have to use a magnesium(carbonate) supplement(Epsom Salt). Magnesium is recommended to be 3 times the calcium level, but I keep it around twice the calcium level, at 1300ppm. I also have to watch my alkalinity and pH. I do use a pH buffer by Seachem to keep it stable. There are additives made by Seachem, API and other companies that will take the calcium levels down but as I said there really isn't a need to do so. The high calcium levels will benefit hard corals, inverts and coralline algae growth and they arent high enough to damage any life in your system. You may have what is called precipitation(white calcium deposits on the powerheads, pumps, etc) that require some cleaning, but more than likely not. As I said 512 is not that high. Make sure you also have other essential minerals as well. Iodide, strontium etc. All are necessary to a healthy reef. You can buy bottled Ro/Di water for your water changes to lower the calcium levels as well. But as I said, it's not an issue as long as you maintain alkalinity/DkH and pH . Just test regularly(every 2 or 3 days, since it's a new system) and enjoy. You should start seeing amazing coralline growth in the near future. Below I've included some guidelines below for mineral levels for reef keeping as well as DkH and pH. Let me know if you have any more questions or if I can help further.

pH: 8.2 - 8.4
Alkalinity/DkH: 7 - 12
Phosphate(PO4): Less Than < 0.13 ppm  
Calcium:  380 - 480 ppm  
Magnesium:  1250 - 1300 ppm  
Iodine:  0.06 - 0.10 ppm
Strontium:  8 - 14 ppm