Category Archives: slow sand water filter study and construction

Water can be tested by using kits available from this source:  Micrology Laboratories. Their website has the information necessary to understand how to use the test kits. Tests can be done for E coli, Coliform, and Aeromonas bacteria. Their website has a … Continue reading →

Here is some interesting information about slow sand filtration and rainwater harvesting: A study documented by the University of Cincinnati has shown that the Mayan civilization knew about using sand for water filtration. In Washington state, King county officials have … Continue reading →

This is a summary of 6 years of experience building operating and testing small slow sand water filters. There have been a significant number of failures which have been good learning experiences, subsequently resulting in astounding successes. The failures are … Continue reading →

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 … Continue reading →

The pond filter works, quite well. It has up to this point been fairly “biomatic” that is to say, the filter has not needed cleaning (although I have wet-harrowed it several times) and has worked with naturally occurring biological removal … Continue reading →

Just a thought about catching rain water to use in an emergency (I have to have a rant once in a while). . . . It could easily happen. An emergency situation due to an earthquake, a power outage, or … Continue reading →

The water clarity of the output from filter 4 has been getting worse and worse up until 2 days ago. An air vent on the top of the barrel was added after I noticed the output pulsing while the pump … Continue reading →

When the filter was first set up the flow rate was too fast, a regulator valve was added. .25mm sand on the top 4 inches;  .45 mm sand bottom; pea gravel bottom 4 inches;  carbon granule filter on output;  3 … Continue reading →

Compared to the other filters I have put together, this one is slightly different. The majority of the sand is .45 mm effective size. This filter appears to be more subject to variations in the input water quality. Heavy rain … Continue reading →

Feb. 28 6:30 AM PST: The output water directly from the filter is now perfectly clear based on visual inspection. The filter did not freeze last night, although the temperature was 30 degrees F. Feb. 27 5 PM PST : … Continue reading →