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1 minute read
Dosing by Calcium explained
Since all of the 36 Major, Minor, and Trace elements including the Alkalinity are used up in a relatively fixed ratio it may seem logical that the Complete Reef Care supplements can be dosed based on a measurement of the Alkalinity instead of calcium, however, this does not work.
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Almost all the calcium and most of the other 36 elements are taken up exclusively by the biogeochemical processes of the corals and therefore there is a direct relationship between coral growth and the calcium uptake.
The carbonate and bicarbonate alkalinity components that are used by the corals to form their skeleton are an important part of the Total Alkalinity of the aquarium water, however, the measured Total Alkalinity also includes the Alkalinity of many other components such as borate, phosphate, fluoride, silicate, sulfate, nitrate, and organic compounds.
These other components of total Alkalinity are easily affected by many non-coral related processes such as water changes, foods, supplements, build-up of organics, and by-products of bacterial activity. Furthermore, there are other biogeochemical processes such as photosynthesis and nitrification that also consume carbonate alkalinity components.
Dosing all 4-parts based on the uptake of alkalinity will also dose the Calcium and other elements that were not depleted by calcification. This will lead to higher concentrations of Ca and other trace elements that will cause precipitation and a drop in alkalinity that will break the delicate chemical balance of the water. On the other hand, corals have the ability to regulate the carbonate alkalinity inside their calcification centers and are able to adapt to slight changes in the Alkalinity of the aquarium water.
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Sharon Ram
Red Sea’s Chief scientist