Calcium Magnesium Acetate.

[robash]

Has anyone used CAM for replacing magnesium?

If all of the salt is acetate, won't that be converted to alk instead of raising the sulphate or chloride?

[Randy Holmes-Farley]

Yes, and that wouldn't be good, except for exact routine maintenance,not significant boosts.

Neither the mixed salt that you mention nor magnesium acetate is suitable for raising magnesium, as it will boost alkalinity way up for each unit of magnesium. It is the same problem as using magnesium hydroxide or dolomite in a reactor. All can be used to maintain magnesium, however.

I discuss that there:
Magnesium
http://www.advancedaquarist.com/issues/oct2003/chem.htm


from it:

"It has been suggested that adding dolomite to CaCO3/CO2 reactors can help with magnesium problems. Dolomite is a material that contains both magnesium and calcium carbonate. If dolomite is being added to the reactor to maintain existing appropriate magnesium levels against the continual depletion via calcification (for example, if the calcium carbonate being used is too low in magnesium to maintain adequate magnesium) then this is a fine approach.

However, this method is unsuitable if the goal is to raise magnesium levels. The problem is that for every magnesium ion released from the dolomite, 2 units of alkalinity are also released:

MgCO3 --> Mg++ + CO3--

Consequently, if one wants to raise magnesium by 100 ppm, the alkalinity will necessarily rise by 8.2 meq/L (23 dKH). The only way around this problem is to add a mineral acid (not vinegar) to the aquarium to reduce the alkalinity, and that may be more problematic than just adding magnesium in the first place."

Here's a DIY magnesium supplement:

Do-It-Yourself Magnesium Supplements for the Reef Aquarium
http://reefkeeping.com/issues/2006-07/rhf/index.php