Candle filters require frequent maintenance. Because of particle build up and the resulting reduced flow rates, filters must be cleaned with a soft brush and clean water every 2 weeks (Dies, 2003). After successive cleanings, the ceramic candle tends to lose wall thickness and becomes less effective for removing microbes (Clasen and Boisson, 2006). The service life of candle filters vary, but they should be replaced every 6-12 months (Clasen and Boisson, 2006; Dies, 2003).
Ceramic candle filters are fragile and must be handled with care. Even the slightest crack will reduce the microbiological removal effectiveness of the device. Surveys of candle filter users noted that many people stopped using them because of breakage. Those who owned broken filters rarely bought a replacement filter and went back to using untreated water (Clasen and Boisson, 2006) whether replacement filters were available or not. Training, although not extensive, can promote proper maintenance and use of candle filters. Some shop owners who sell these filters teach consumers how to operate and maintain their new filters (Dies, 2003).