? about calcium mine keeps staying solid!!!

[asiankidd2]

ok well i have a mature tank with lps and sps, along with a clam. I do semi regular water changes and everything seems to thrive but my calcium just doesnt ever dip lower than 420...i do not dose anything and yet i can go for a whole month with out a water change yet my calcium stays in the mid 400's what gives? my parameters are also solid. Does anyone happen to know if calcium jumps up and down? i usually test when my lights are on and in the day time but does anyone have any input, i test with the salfert and aquarium pharm. kit both seem to confirm each other.

24 gallon
35lbs of lr
25 lbs of live sand agaronite sand.

thanks

[old salty]

I wouldn't consider this a bad thing; stability is good. About six weeks ago, I changed salts and have since cut my limewater saturation in half and have completely removed my calcium reactor from the system. All parameters are dead on, corals are happy and growing well.

[asiankidd2]

so where does my calcium come from? i have a clam and 5 sps coral frags 2-2.5 inchs plus other lps corals all seem to be growing.