Sodium hydroxide is Lye, the stuff commonly used for drain cleaner, a very strong base (alkali). Sodium hypochlorite is household chlorine bleach (usually about 3% - 5%). The bottle of Clorox "rain clean" under my sink has both listed on the label, but no indication of strength. -Denny I currently use a spa pool chlorine with the active ingredient "sodium dicloroisocyanurate" 600g/kg I have been told a may be able to use another product sold as Janola with the active ingredient "sodium hypochlorite" 4.2% & "sodium hydroxide" 4% Any of you chemical wizards able to tell me if this is ok to use in a spa pool? I contacted the Janola distributor but they would only say to use as directed which does not include spa pools. Roy :-( -- http://www.piclist.com hint: The list server can filter out subtopics (like ads or off topics) for you. See http://www.piclist.com/#topics