calcium depletion?

[sw-addict]

I have a question about the calcium depletion in my 120. I check my water parameters weekly or close to it and the calcium never looses more then 20ppm and alk may drop 1.1dkh. Now last weeks tests were salinity 35-p.h.8.2-nitrite0-amonia0-nitrate0-calcium440ppm-alk9.5-temp80 and if you care about kh11. now this weeks salinity35-p.h.8.2-nitrite0-amonia.25-nitrate0-calcium330-alk7-temp80 and if you still care kh13. The only new addition to the tank is a saddle carpet nothing has died I replaced the carbon and cleaned the tank the day of the first tests but only 10%. Tank inhabitants are 3 tangs, madarin dragonette, neon goby, skunk cleaner shrimp, orange linkia star, tuxcedo uchin, pink pincusion somwhere around 50 blue leg hermits and 4 snails also small bubble tip orange ricodia 7 other small unidentified ricordia and around 25 red mushrooms. I also have added 1 maxi-jet 1200. I guess when I look back over my records that a 50ppm calcium drop after water change is normal scince I dont add calcium to change water but I will start now. I also drip kalkwasser daily close to 2 gallons. Anyway what is eating the calcium in my tank?

 

[Biggen]

Anyway what is eating the calcium in my tank?

Do you have a lot of coralline algae growth recently? I know in my tank, the coralline algae explosion I am going through is taking out large amounts of Alk and Ca from my water. I have to replenish them every day.

What are you referring to as "kh11" and "kh13"? Are you meaning gh??

As an aside, what caused your ammonia to increase to .25ppm? Unusual to happen in a cycled tank.