Organic pools bubble flow. How a natural pool is pumped with one airstone in 1/2 day..

David Pagan Butler, inventor of the Organic pools bubble flow circulation system, shows how different diameter pipes work as air-lift pumps.
Free pdf: www.organicpools.co.uk/DIY%20DVD.htm
And have a look at the great variety of DIY Organic pools David has inspired: organicpools
You can buy David's classic DIY film "Make a Natural Swimming Pool":
vimeo.com/ondemand/organicpools