Is it Reef Advantage Calcium or just Reef Calcium?
The Reef Advantage also includes magnesium and strontium to help balance out the
ca. The Reef Calcium is strictly
ca and your
ca level could be off due to just adding that and not magnesium and strontium.
If you have only done it once you probably haven’t hurt anything assuming you followed the directions. If you have been adding for weeks your
ca could be off the chart and you may need to do a couple of 20%
pwc.
Most salt brands are low in
ca and often need additional
ca additives if you have corals that require
ca. As everyone mentioned you should never add to your tank unless you know you need the additive through testing though.