Tears of the crocodile

Tears of the crocodile was a spell that turned freshwater around its caster into saltwater. The reverse form, tears of the alligator, would turn saltwater around its caster into freshwater.

Effects
This was centered on its caster and would alter the water within a radius of them. Creatures of an animal intellect that inhabited the water were repelled from its altered counterpart, while more intelligent creatures were capable of entering it, albeit with discomfort.

Components
In addition to a verbal and somatic component, this spell required a material component in the form of three crocodile tears sealed within a hollow ceramic sphere. The reverse form, tears of the alligator, instead required three alligator tears sealed within a hollow ceramic sphere.

Notable Users
Greater sea hags were typically able to cast this spell.