he oocysts from the fecal debris by either salt flotation using sodium sulfate or gas flotation using air,...http://www.google.com/patents/US7229615?utm_source=gb-gplus-sharePatent US7229615 - separating the encysted protozoa from a suspension containing the encysted protozoa by either a salt flotation process where the salt is salts such as sodium sulfate, magnesium sulfate, magnesium chloride, c