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Re: Measures

>Ok so call me a little slow BUT........what the !$@!
>is meq/l ???????????? this has been used extensivly in
>the thread: "Equilibrium, Ca and Mg levels" is this
>suposed to be mg/l ??????

Brief background: 1 equivalent in chemical terms means you have 6.02 
x 10^23 molecules or atoms of that particular chemical compound.

But that's a pretty big number, so think of like this: 1 dozen is 
twelve items. If I have 1 dozen chicken eggs and 1 dozen ostrich 
eggs, then which item do I have more of? In chemical terms I have the 
same quantity of both items; I have one dozen of each. You can also 
say I have 1 equivalent of each (the quantities are equivalent). If I 
answer in terms of mass, then I have more of ostrich egg.

Plants don't care how much these elements weigh, they just need a 
certain quantity. So if you say you have 40 g of calcium and 24 g of 
magnesium you might think you have more calcium than magnesium, but 
you actually don't in terms of numerical equivalence because 1 
equivalent of calciums has a mass of 40 grams and 1 equivalent of 
magnesium has a mass of 24 grams; therefore you have exactly the same 
amount of magnesium as calcium.

And the "m" of meq/L means "milli", so that just means 1/1000 of an 
equivalent. It's just easier to say 1 meq/L than 0.001 eq/L.

BTW, you can convert meq/L to mg/L by multiply the meq/L number by 
the molecular weight of the chemical in question. So 1 meq/L of 
calcium is the same as 40 mg/L of calcium.

-Greg Morin

Gregory Morin, Ph.D.  ~~~~~~~Research Director~~~~~~~~~~~~~~
Seachem Laboratories, Inc.      www.seachem.com     888-SEACHEM