Read this article on Mollies, Guppies, Platys, Swordtails, Four-Eyed Fish (Anableps).
http://animal-world.com/encyclo/fres...ivebearers.htm
scroll down to where it says;
"Care and feeding:
Livebearers generally enjoy harder water, and will benefit from 1 to 1.25 teaspoons per gallon of...