wrote in message
...
roughly...
1/2 cup salt in 1 gallon = 3%, the concentration for a dip.
1/2 cup in 10 gallons = 0.3%
1/2 cup in 30 gallons = 0.1%
10 x 1/2 cup or 5 cups of the course rock salt used in water softeners
will give you
about 0.1%
snip

Don't you mean a minimum of 0.1%? Does the OP know the current salinity of
the water?

BV.
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