Magnesium is at 1200.
Alkalinity at 7
Calcium is around 380-400 said:
Generally, you want your Mg at 3x your target Ca level. So if you want a Ca level of 450 ppm you'll want your Mg at 1350 or a little higher. High magnesium levels can be harmful to snails. You'll want to take your Mg salts and mix it up into a solution before adding it.
Raise your Magnesium to your target levels first as that is what helps keep the Alk & Ca from precipitating out. Give it 12 -24 hours after dosing to verify levels.
Do not try to raise your parameters too quickly (mainly Alk as that can cause a pH spike). The general rule of thumb is 100ppm of Mag daily, 0.5 dKH of Alk is safe although I've raised Mg by up to 300ppm in one day without an issue (so long as salinity is kept stable, see below). I''m not sure I've seen a guideline on how much to raise Ca at once but I would think 25 - 50 ppm a day would be safe.
Then, as Eckolancer said, monitor your daily consumption and dose accordingly. If the changes are too small to note on a daily basis, wait about 3 - 7 days without dosing that particular parameter and divide by the number of days to get your daily dosing rate.
If you find you are dosing a lot, you will want to make sure you monitor salinity and keep up with water changes as a lot of solutions will raise your salinity as you go. I think most Mg solutions are salt based as well as a bunch of the calcium supplements.
