I think one 5000 gallon swimming pool would take about a 50 pound sack and you would be just under one tablespoon per gallon. I used about a heaping teaspoon I think in my aquariums.

I read that salt kills algae. I never had a problem growing algae in my aquariums at the level I used. Do you guys think using a whole tablespoon per gallon would still grow lots of algae?