HOW OFTEN TO CHANGE FILTERS:
The determination of how frequently to change a filter element should always be based on how much water has passed through the filter.
David Getoff recommends the following for an “average” family of three or four persons who do not drink huge amounts of water and who do not also use their filtered water to water their plants.
For the Twin above counter or below counter system in non-fluoridated water, if your first filter is a carbon block and the ceramic filter is second, then replace the carbon block once a year and the ceramic every 2 years.
HOW TO INSTALL THE FILTERS:
From the faucet, the order of the filters varies depending on the water supply as follows:
Normal set up for water which is chlorinated but does not contain fluoride or chloramines (you may need to call your water company to find out if your water has fluoride or chloramines in your water):
1. First position (tap water goes through this cartridge first) AquaMetix carbon block
2. Second position is the CeraMetix ceramic cartridge