locking mechanism 78 are feasible preferred embodiments of the apparatus of the present invention having been described in the foregoing operation of the water dispensing apparatus 10 will be described first the user fills the water container 12 with water such as tap water once the container 12 is filled to the desired level e g until full a new cap 24 is placed on the neck and mouth of the container 12 as indicated in fig2 this cap 24 can be conventional in design and configured to prevent water from flowing out of the container as the container is inverted and placed on the dispensing unit 14 typically the cap 24 is made of a plastic material and is scored or perforated such that the probe 22 will puncture and or pierce the cap to open the flow of water from the container 12 to the filter 22 a preferred embodiment of the cap 24 is shown in fig2 28 as identified in fig2 the cap 24 is substantially cylindrical and has a base 100 as shown in fig2 and 28 the base 100 includes an indentation 102 that is adapted to receive the probe 22 of the adapter 18 or 18 u2032 normally for sanitation reasons the indentation 102 is covered with a rupturable membrane 104 fig2 that for instance is provided with score lines 106 that facilitate its rupture the indentation 102 is formed by a frusto conical member 108 that is best viewed in fig2 this member 108 is sized and configured to receive the probe 22 and as identified in fig2 is also.