I like turbo calcium. I add it every day in the a.m. when I get home from work. Easy. Liquid is good too. Euther way, just as long as it maintains your levels 450-ish ppm and it easy for you.
Got Milk? Now thats funny...( I am the milk man!!!!!)*_^
I use seachem reef advantage..reef builder..and kalkwasser to build as well as maintain calcium & alkalinity levels. I would not use anything not specifically designed to be used in marine systems.