source of high calcium

[Beverly]

Originally Posted by reef_raf

if it's that low, a whater change should do it.

Depends on how much water is changed. A 10% water change will not increase calcium that much, imo.

Here are some articles to read. Heavy reading at times, but will help you understand reef chemistry better:

Solving Calcium and Alkalinity Problems:

http://www.advancedaquarist.com/issues/nov2002/chem.htm

Magnesium in Reef Aquaria:

http://www.advancedaquarist.com/issues/oct2003/chem.htm

Reef Chemistry Calculator:

http://home.comcast.net/~jdieck1/chem_calc3.html