Slow sand filter functionality

This is an update on the operation of Filter 4 (see details of construction in the post on November 13, 2011). It has been in operation for six months now. At this point in time it is producing very clear water and the flow rate has stabilized at about 30 litres per hour (.130 m/hr). Another water test will go in as time and finances permit. Over 4000 liters (about 1000 gallons) of water have been filtered in the past 3 months as a result of only rainwater flowing from the 100 square foot roof of the adjoining building.  A YouTube video on the construction of this filter is in the works and I will have it up (hopefully) within the next couple of weeks. More later . . . .   .