ZeoPlus should be regenerated once it is saturated i.e. full of ammonium. On an average pool this takes around 12 months, although heavily used spas and hydrotherapy pools may require regeneration sooner. ZeoPlus should be regenerated once ammonium level 
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ZeoPlus is a naturally occurring mineral rock, found in areas where there has been historic volcanic activity. Its microporous structure and ammonia removal properties will significantly improve the quality of your swimming pool water. 
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