Sagan Life Filter Technology - How it Works
The patented filtration media technology used in all Sagan water purification products is based on electro-adsorption of contaminants, not mechanical filtration. The electro-positively charged media acts like a magnet attracting and retaining contaminants, as small as viruses, out of the water as they come in contact with the media.
The media itself is made of layers of non-woven, nano-alumina coated glass fibers containing powdered activated carbon (PAC) and antimicrobial protection (silver). The positively charged media field is sandwiched between layers of spunbond polyester, which provides strength to the pleated media.
The proprietary filter media offers exceptionally high flow rates and efficiency in removing contaminants. The media has been shown to remove viruses, bacteria, cysts, volatile organic compounds (VOCs), disinfection by-products, endotoxin, natural organic matter and other sub-micron particles.
So, there are a number of facets to the Sagan filters namely.....
> Nano filtration paper infused with silver (silver has antimicrobial properties)
> Powdered Activated Carbon (PAC): improves taste, odor and clarity by the absorption of chlorinated compounds and disinfection by-product
> The Captivator Adsorbtion Media (CAM) is an electroadsorptive filter. Due to its crystal structure, the mineral Pseudoboehmite (within the filter) creates a natural, strong positive charge which attracts the negative charge present on most submicron contaminants. This reduces a wide range of submicron particulates, pathogens, trace pharmaceuticals and cellular debris, making water safe to consume. For example; for a nasty particle to pass from one side of the media through to the other, it has to make its way through a minefield of approximately 400 layers of fibers/pores.
Some science HERE if you need it. ;-)
How do I know when the filter needs replacing?
Technically, the filter never stops filtering and purifying the water. However over time, the filter may become clogged up from dirt, etc. and it may become difficulty to drink through. If this happens, you need to replace the filter. Remember that even though the flow rate might be slow, the water is still purified and clean :-)
If filtering clear water (as opposed to cloudy, turbid water) then the filters will last for a very long time!