Inside a large, hand-made oven they bake pot-like ceramic filters made from clay and sawdust which are then fitted within plastic tubs of various capacities. The filters are impregnated with colloidal silver, a natural antibacterial and provide an ecological alternative to boiling or chlorinating.
The method, first developed by Guatemalan scientist Fernando Mazariegos back in 1981, allows water to be drawn from contaminated lakes and rivers and then safely consumed after the filtering process.
The 20 litre 'community-sized' tub costs $37.
Ecofiltro has received a World Bank Marketplace Award for sustainable technology and is now also manufactured in 13 countries outside of Guatemala.