How to raise Mag to increase Calcium??

[chuckdallas]

According to Skat8r's signature line here on RC, he says that you can't increase alk & calc, if the magnesium is low.

According to the Red Seas Mag test kit I have, I'm getting 1080 & the conversion chart says for my size tank, I should be at 1280 or so.

My calcium has been steady at 350 ppm, so I bought the 2-bottle B-Ionic Calcium Buffer System and started using that since Saturday. I know anything bad can happen quickly and nothing good happens fast, but the calc is still at 350 ppm after 4-5 days with the chemical additives in a 120 gallon tank and 30 gallon sump. I have read here that most of the hobby grade test kits are not THAT reliable, so I'll take a water sample to the LFS, probably using the same test kit, to verify the mag, alk and calc.

We got a small clump of what was called a Colt Coral this past Friday, a small rock with 5-6 Mushroom softies and Chili Coral on Sunday. We have 3 Gorgonians too, but no hard corals, unless the Gorgonians are considered a hard coral.

I'm using a 2 bulb T5 HO fixture with an ATI Blue Plus and an ATI Aquablue Special, in addition to an older T5 HO fixture with 4 bulbs. The bulbs in the older fixture may be 6-7 months old (as I was told), so maybe they need to be replaced. I'm working on ordering some more ATI bulbs soon. I run the blue lights only from 1 pm to 2 pm, the white & blue lights from 2 pm to 8 pm, and then the blue only from 8 pm to 9 pm.

Question #1: Can I buy just a bottle of Kent or Salifert Magnesium and add that? Recommendations of other brands, if these are not recommended?

Someone gave me the link to the online Reefkeeping Magazine Reef Alchemy article from Randy Holmes-Farley's' Reef on how to mix you own alk, calc & mag solutions. He mentions that users of his recipe should add the magnesium AFTER the alk & calc solutions.

I'm no chemist (although I play one on TV).

Question #2: Alright you no kidding Marine Biologists, what's the difference between adding it before and/or after the alk and calc soltions?

Questions #3: Why does the B-Ionic say to add the Alk first then the Calc? This is probably another chemical reaction related answer. Duuuhhh. God, I hated that class in college, which is the main reason I didn't become a doctor and instead became a pilot.

Thanks in advance.

[Toadally]

You can use a mag supplement such as BRS magnesium to raise it. Don't raise it more than 100ppm per day.

[disc1]

The reason they tell you to add alk first then calcium is because if you add the calcium first and then add alk, the locally high concentration of alk (right in the spot where you added it) will cause precipitation of calcium. If you add the alk first while the calcium is a little lower, then this doesn't hapen as bad.

[bertoni]

1) The Kent and Salifert products are fine. I have used both. The BRS might save some money.

2) The magnesium level you mentioned is all that bad, so the order doesn't much matter. I would make sure that the alkalinity supplement hasn't spiked the pH very much before adding the calcium, though. If the magnesium level is very low, that can allow calcium and alkalinity to combine and precipitate, so in some cases, magnesium should be added first.

3) The order doesn't matter, as long as the parameters are reasonable and the dose is reasonable. Large doses of alkalinity might need to be spread out over time if the supplement is high in pH.