IMPORTANT CONSIDERATIONS ABOUT SEA SALT MIXES FOR MARINE AQUARIUMS

Although it is often taken for granted that sea salt mixes on the market are generally the same, this is not true.  If you are interested in seeing how different they can be, see the classic technical book on this subject by Joseph P. Bidwell and Stephen H. Spotte, "Artificial Seawaters Formulas and Methods," published by Jones and Bartlett Publishers, Inc., Boston and Woods Hole 1985, 349 pp.  Their research was done at the Mystic Aquarium in Connecticut and the Woods Hole Oceanographic Institution in Massachusetts. 

What has to be considered in choosing a sea salt mix are:


*   What Is The Water Source You Are Going To Use?
*   For A Sea Salt Mix What Are The Grade of Elements Being Used?
*  Just How Tolerant Are Coral Reef Fishes And Other Coral Reef Animals To Variability In     The Elements In The Fresh Water and Sea Salt Mix Used?

What Is The Water Source You Are Going To Use?

If it is tap water, keep in mind that tap water varies widely, particularly in hardness across the United States and elsewhere.  Tap water already has a lot of major, minor, and trace elements in it.  How does your source fit in with the sea salt mix you plan to use?  Will the major elements, for example, be in oversupply, compounded from being from both the tap water and the sea salt mix?  For an understanding of just how variable water hardness is (fundamentally based on calcium and magnesium hardness), see the report by the U.S. Geological Survey http:/ga.water.usgs.gov/edu/characteristics.html. 
 
If it is deionized or distilled water that is going to be used, then the sea salt mix should contain everything that is needed in elements.  That is a big difference between using pure water (hydrogen dioxide) otherwise element free, and tap water in which no two localities are likely to be the same in over 100 elements present in the water.

For further information on this subject see Kordon Article "What the Beginning and Advancing Aquarist Absolutely Needs to Know and Do When Starting an Aquarium", and go to the last group of topics on marine aquarium keeping.

For A Sea Salt Mix What Are The Grade of Elements Being Used?

Ocean water  contains 78 elements besides pure water (Hydrogen dioxide), which may be classified as major, minor, and trace based on their amounts of concentrations in sea water. 

The major elements in sea water  at  concentrations of 3880-19,000 mgL are Chloride, Sodium, Sulfur, Calcium, Magnesium, Potassium at concentrations of 380-19,000 mgL

The minor elements in sea water at concentrations of 2.5-28 mgL  are Sulfur, Potassium, Carbon, Nitrogen, Bromine, Boron and Silicon (or down to 0.12 adding the following as minor elements):  Fluorine, Strontium, Lithium, and Rubidium

The trace elements in sea water at concentrations of less than 0.07 mgL are all the rest.

The quality and costs for the different elements to use in sea salt mixes can widely vary.  If the manufacturer is cutting costs, the more costly elements or compounds may be absent, or the wrong compound may be used, such as the sulfate (cheap) versus the chloride (expensive) form.  The cheaper form will get by, most aquarists not noticing the difference.  But is this what the marine aquarist with expensive fish and equipment is expecting?  Also, to the benefit of aquarists, most sea salt mixes on the market contain organic compounds, which in the right form are important health aids, including vitamins which vary widely in composition between the different products. 

What Kordon did for its Coral Sea sea-salt mix is follow the advice of the researchers at the Woods Hole Oceanographic Institution Massachusetts, where research was being conducted on sea salt formulations for aquarium keeping for both the inorganics and organics in the formulations.  Coral Sea salt mix does not skimp in using the right more expensive compounds of the elements and organics.   Kordon's Coral Sea is compatible with using it on a wide range of tap water conditions

Just How Tolerant Are Coral Reef Fishes And Other Coral Reef Animals To Variability In The Elements In The Fresh Water and Sea Salt Mix Used?

While fresh water conditions on land, even just a few miles apart, may be greatly different in the concentrations of major, minor, and trace elements, this is not the case for coral reefs around the world in the tropics.  There conditions are fairly uniform, including in all having the same pH (8.3 declining towards 8.2, the decline from 8.3 apparently due to global warming), and composition of the elements in the water.

The question becomes just how tolerant are fishes and coral reef life to all of these variations when a sea salt mix is put with local tap water for them to live in?  What has been found is that it varies with the organism.  As pointed out by Bidwell and Spotte, the simpler the organism, the more complicated and complete the artificial sea water needs to be to accommodate them.  "Algae, for example, obtain all their nutrients from the surrounding solution.  In contrast, fishes derive nearly all of their nutrients they require from food and survive satisfactorily in artificial seawaters that only approximate seawater in terms of major ion compositions."  Bidwell also pointed out in his research that invertebrates, such as sea slugs, would not grow or reproduce if certain trace elements were lacking from the water. 

The real problem in coral reef aquarium keeping is in the marine invertebrates (shrimp, crabs, coral, anemones, starfishes, etc.), particularly for the quality of the trace elements in the water, which if lacking or in short supply will interfere with the animals' health and survival.  The regular addition to the water of trace elements and vitamins to replace those used up is essential.  It is recommended to use Kordon's Saltwater VitaTrace for this purpose (there are both marine and freshwater versions).


For those who remember when Kordon had "Wonder Water" will understand just what a wide tolerance there can be in water conditions for tropical fishes, both marine and fresh water.   Wonder Water was a unique combination of compounds that allowed both freshwater and marine fishes to live in the same water environment.  In fact, marine coral reef fishes did very well, and beat up unmercifully on the freshwater tropical fishes, with their scales flying off, and scurrying for cover.  Kordon could not find a sufficient number of species of freshwater fishes that could survive the marines' aggression, and the product had to be discontinued.  Even Jack Dempsey cichlids could not hold their own against the coral reef fishes, including against some of the small damsel pomacentrid fishes. 

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