is this posible, 2 different test have concluded his calcium is very high, both where salifert test. one old thought that might have been the problem so got a new one but got the same reading 650. he dosnt dose extra calcium in the tank. water changes once a month has a small amount of corals. his dkh is normal dont remember the number off hand. he has a 55 with compact lighting. any suggestions why this might be?