Your consumption is pretty low and will increase as you add more coral and they grow. High calcium really has no effect on your system or coral calcification. However, if it gets too high it will depress your alkalinity to dangerous levels.
If your testing calcium in a fresh batch of salt water and it’s coming out that high, there is only two causes. 1- not likely - the batch of instant ocean you got was messed up during manufacturing and too much sodium bicarbonate was added. 2- likely - Your not mixing the salt up enough before you mix it. If your not already dumping your salt into a bucket with a lid I would highly recommend it. Once you put the lid on tight roll and tip the bucket upside down over and over before you add it to the water change barrel. Additives / elements Ect are weighted differently and will sink to the bottom. Just a suggestion.