The Life Sack purification system is a concept that is not currently in use.  We use this concept in the Type B system.  We think it works well as a basic first step filtration system to kill some harmful bacteria with the UV rays from sunlight.  In our model the drainage system is located in the middle so that particulates in the water settle at the bottom.  

Our Life Sack like concept then has tubes (water flow is manually turned on and off) that connect to a modern but highly affordable water purification system similar to the Greenway water purification system as shown below.  The filter lasts for about 6 months. There should be no compromises with providing clean water for people, we think this is one of the most practical solutions we have seen thus far.