Yeah, the flavor text at the beginning of the game says this:
Ice, alchemy and aquiatic beings are under the control of water elementals. Some examples of water elementals skills are: “freeze”, “ice bolt”, and “purify”, which is used to remove poisons. Water elementals have a good balance between offensive and defensive skills.
Nymph's Tears produces a nymph, which has the ability of an alchemy card. So the ability to produce nymphs should definitely be Water.