staindsoul
10/04/2012, 05:49 PM
I have a question on calcium and alkalinity levels, depletion and testing. The reefkeeping article on their relationship states this:
1. Corals and coralline algae use calcium and alkalinity almost exclusively to deposit calcium carbonate. Because of this they use a fixed ratio of calcium to alkalinity, which is driven by the ratio of calcium and carbonate in calcium carbonate (1:1). The net consumption is about 18-20 ppm of calcium for each 1 meq/L (2.8 dKH) of alkalinity. The reason the amount of calcium varies is that the incorporation of magnesium in place of calcium varies a bit from species to species.
2. The fact that corals and coralline algae use a fixed ratio of calcium to alkalinity allows supplements to be devised that mirror this exact ratio. Using such an additive system allows accurate matching of the supplement to the demand, and does not cause rapid swings in calcium or alkalinity relative to each other if the additions are not perfect. Such balanced additives include calcium carbonate/carbon dioxide reactors, limewater/kalkwasser and two-part supplements, among others.
Hypothetically, if I only use 2 part for dosing and corals and coralline used a fixed ratio of both. Can I only test for alkalinity and trust that the calcium parameters are good?
I'm not saying cut testing calcium tests out completely, but cut back to weekly or even monthly. Does anything else deplete calcium out ratio w/calcium?
Sidenote question: how often do y'all test for magnesium?
1. Corals and coralline algae use calcium and alkalinity almost exclusively to deposit calcium carbonate. Because of this they use a fixed ratio of calcium to alkalinity, which is driven by the ratio of calcium and carbonate in calcium carbonate (1:1). The net consumption is about 18-20 ppm of calcium for each 1 meq/L (2.8 dKH) of alkalinity. The reason the amount of calcium varies is that the incorporation of magnesium in place of calcium varies a bit from species to species.
2. The fact that corals and coralline algae use a fixed ratio of calcium to alkalinity allows supplements to be devised that mirror this exact ratio. Using such an additive system allows accurate matching of the supplement to the demand, and does not cause rapid swings in calcium or alkalinity relative to each other if the additions are not perfect. Such balanced additives include calcium carbonate/carbon dioxide reactors, limewater/kalkwasser and two-part supplements, among others.
Hypothetically, if I only use 2 part for dosing and corals and coralline used a fixed ratio of both. Can I only test for alkalinity and trust that the calcium parameters are good?
I'm not saying cut testing calcium tests out completely, but cut back to weekly or even monthly. Does anything else deplete calcium out ratio w/calcium?
Sidenote question: how often do y'all test for magnesium?