Just checked my tank log today and realized I havent checked the alk or calc since December. After switching back to instant ocean from reef crystals I had been struggling keeping my calcium level up as I never spike the fresh salt water. Getting tired of the chronic 340-380 calc range with alk around 8 I stopped testing back in December. Since then the tank has puddlled along just fine and growth has remained the same. I haven't changed the two part ratio, keep kalkwasser at the bottom of the ATO tank, and do a couple 5-10% water changes a month. The only parameter I have measure since December is salinity. Just goes to show that running a tank doesn't have to be a science experiment with testing once things settle in. That being said I think I'm going to check the calc and alk tonight when I get home from work. I'm sure my calc and alk are low, but it obviously doesnt kill corals like some would have you believe.