I have been keeping reef tanks for a year and I still know nothing. Now that is out of the way heres my question. I have at the moment a 60 gallon deep blue rimless frag tank. Using my CO2 scrubber I am going through ALK pretty quick. I dose 0-60ml a day depending on the level to maintain close to 8.6 dkh. My question is I have never had to add Calcium and my level stays 550-600 with my hannah tester with water changes alone. Is this normal?