Adding Cal and Mag to IO salt
 

I was just wondering whats the best product to use is if I want to add calcium and magnesium to Instant Ocean

Check out the Chemaster's products. I have ordered from him a few times. Good product and good prices.

Have you tested your mixed IO salt water for Ca and Mg? What are the numbers? What do you want them to be?

I use his products. Follow his mixing amounts also, which I think are based on Randy,s writings from RC.

do find the numbers vary a bit pail to pail so I'll get my amounts from this calculator, target here (NSW)

I also use littlesilvermax's stuff

Most people just use generic no-name pharmaceutical grade calcium chloride and a mix of magnesium sulfate and magnesium chloride. ChemMaster, Bulk Reef Supply, Ocean Aquatics and Oceanic Corals along with numerous others sell them these days.