PermaClean 77 is a membrane cleaner specifically designed to remove iron fouling. It also has effectiveness against light calcium carbonate scaling. The efficacy of PermaClean 77 can be enhanced by the addition of PermaClean 33 to the cleaning solution although some minor pH correction may be necessary. PermaClean 77 should always be used as recommended by the membrane manufacturer or equipment supplier, in respect to cleaning pH and temperature.