ml> what purpose does the salt serve? i've never added salt 
 ml> of any kind to my tanks... at least, not knowingly...
There is some belief that the salt will help fight certain diseases.  I have 
heard that this is an old wive's tale with no scientific proof, but I also 
know that old wives tend to be pretty smart.  I have one tank that has 
suffered significantly more deaths in recent months than my others.  When I 
tried to figure what the difference was, I discovered that y wife had not 
been replacing the salt when she did a water replacement.
Also, some fish, particularly mollies, tend to thrive better with a little 
salt in the water.
Robby
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