The DLM Wallace polyspun cartridges are made from fused and intertwined polypropylene fibres. No chemicals or glue is used in construction.
Fine fibres handle efficient particle removal while coarser fibres give the cartridge structural strength. By varying fibre size and density through the cartridge, a true depth filtration gradient is created, capturing particles of different sizes as water passes through.
5 micron — first stage. This is your workhorse pre-filter, catching the bulk of sediment, silt and rust before it reaches anything downstream (carbon block, UV, appliances, etc.).
1 micron — second stage / polishing. Use this after a coarser pre-filter (or after the 5 micron) to catch finer particles that get through the first stage. Running 1 micron as a lone first-stage filter on heavily sedimented water (especially tank/bore supply) will clog it fast and shorten its life significantly.
So for a typical two-cartridge setup: 5 micron polyspun → CTO carbon, or for a three-stage setup: 5 micron polyspun (1st) → 1 micron polyspun or pleated (2nd) → CTO (3rd).
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