Water treatment system and method

A water treatment system comprising a filter and a filter head;

• the system further comprising a pressure-sensitive button capable of popping when pressure of water flowing out of the filter head is above a predetermined value and sinking when pressure of water flowing out of the filter head is below a predetermined value, the system optionally further comprising:
• an observation portal enabling view of water flowing out of the filter head;
• a release portal for release of gases from water flowing out of the filter head;
• wherein the observation portal, pressure sensitive button and/or release portal are disposed in the filter head;
• the filter comprising:
• a cartridge;
• a cap attached to the cartridge;
• the cartridge comprising:
• a first compartment comprising at least one first water-treating medium;
• a second compartment comprising at least one second water-treating medium;
• the cap comprising a selector;
• the filter further comprising at least one bypass extending from the selector and throughout the first compartment and into the second compartment, each of the at least one bypass having an inlet and an outlet;
• wherein the selector is operable to allow selecting:
• in a first state all water entering the filter passing through the first compartment;
• in a second state all water entering the filter bypassing the first compartment and passing through the second compartment;
• in at least one intermediate state a first part of water entering the filter passing through the first compartment and a second part of water entering the filter bypassing the first compartment and passing through the second compartment, and the filter head reversibly attachable to the cap.