Pure Filtered Water International Ltd. and Oasis Filter International Ltd. own two innovative technologies which capitalize on the strengths of traditional sand filtration technologies while avoiding the main handicaps.

The inventor of the technologies, Dr. David Manz, is an owner and director in these companies.  This website describes the attributes of the technologies in general terms, to provide a context for commercial development opportunities.


The BioSand Filter™

Household Scale Patented Water Treatment Technology

License Opportunities for Commercial Development in Developing Countries

NOTE: Sale of individual filters not available in North America at this time

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For more information on the
MSF or the BSF:

Pure Filtered Water Ltd.
2525 Macleod Trail SW
Calgary, Alberta T2G 5J4

Phone: 1-403-269-1555
Fax: 1-403-264-6244

The Manz Slow Sand Filter

Medium to Large Scale Patent Pending Water Treatment Technology

Suitable for Commercial Development in Mid-Size Communities in developing, emerging and developed countries


The BioSand Filter™ was invented to serve household use with emphasis on its suitability in developing countries. This is a mature technology which augments or creates new markets for established commercial operations in developing countries.

The BSF is a humanitarian breakthrough. Today over 300,000 households in over 100 countries - more than a million people worldwide - are provided safe drinking water from the BioSand Filter™, a product endorsed by the World Bank and World Health Organization. The recent invention of the Manz Slow Sand Filter™ greatly expands the scope of the market for these two complementary technologies..


PowerPoint presentation with photographs of the BSF and information on the technology

Commercial Introduction of The BioSand Water Filter™

Humanitarian Applications

Executive Summary and Technical Information


Dr. David Manz is the inventor of this new technology which is the cumulative result of fifteen years of development work. The design of the MSF is intended to incorporate all of the BioSand Filter™ treatment and structural benefits with a novel simple cleaning process with application for larger scale uses. The MSF is unique as the first sand filter cleaned by fluidizing only the top two layers under low pressure. The ease of cleaning in comparison to traditional slow sand filters provides greater scope in the range of quality of water that may be treated. This allows it to be used in a much wider range of applications than just pathogen removal enabling it to replace more complex technologies currently used as water treatment solutions.


Last updated Saturday June 12, 2010
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