Randy Holmes-Farley
Reef Chemist
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My Tank Thread
Since this thread popped up I’ll share some recent data. Interested in thoughts. The table below is an Oceamo ICP-MS, the Oceamo ideal value ranges, the NSW concentrations and comments from @Randy Holmes-Farley on thread on which trace to dose.
The most interesting ones for me are Fluoride, chromium, and selenium which are around half the concentration found in NSW.
I have no known issues to solve in my tank so I’m not likely to put effort into dosing these separately but it does make me wonder more about their effects. Chromium and selenium are indicated as important biologically but I don’t think I’d know the symptom of having insufficient concentration.
This tank is long term AFR dosing.
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I too do not know the symptoms of lack of selenium or chromium. Both of those will be present in foods, and organisms may possibly get them from particulate matter they ingest (if any). Both chromium and selenium are needed for various enzymes.
Fluoride is nearly exclusively involved in incorporation in calcium carbonate and related minerals in place of carbonate. It has little other role, though a few exotic things have been found. F- is a very stable ion in seawater and organisms have a hard time chemically converting it into anything else. I expect any symptom of fluoride would be an impact on coral skeletons. I do not believe there is any actual data on the effects it has on coral skeletons, I would not even be sure it is a positive effect. That said, maintaining it (and the other two) at natural levels in natural forms (for seawater) is not likely to cause any harm.

). They are also not necessary from my dosing or my salt.