The local AM garden guy is pitching this stuff. http://www.crystalclearchems.com/
Cupric Sulphate Pentahydrate, Zinc Sulphate Monohydrate
Looks to me like an algaecide. I am planning to send him an email directing him to TFP and the hazards of blindly dumping chemistry in. Hopefully I can head some AM radio off at the pass.