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What is a Micron?



Cartridges come in various 'micron' or pore sizes and types of surface areas. The type of surface or micron size depends on what is in your water and what you are trying to filter out. If you need help determining what cartridges you require, Email or text us at 303-736-9856.

  • What is a Micron?

A micron (or micrometer) is a unit of measurement that tells you how small particles a filter can catch. The symbol represents it µ. The lower the micron size, the smaller the "holes" in the filter cartridge that allow water to pass through. Micron sizes range from 150 microns down to 0.1 absolute microns.


  • What is Pore Size Efficiency?

You might wonder, "Why not just use the smallest micron size filter to catch everything?" Well, in most cases, using only a tiny micron filter is inefficient. While it can catch more particles, it traps things like sand and sediment, leading to lower water pressure and more frequent filter changes.

  • Absolute versus Nominal Ratings

Absolute micron filters are rigorously tested in labs and have a rejection rate of 98.6% or higher for the specified micron size. They are typically used as the final filtration stage for sterilizing the water.

Nominal micron filters have a rejection rate of 50-98% for the specified micron size. The effectiveness of these filters can vary depending on the contaminant concentration and water pressure. Most filters are nominal unless stated otherwise.

  • Gradient Density Cartridges

Gradient density cartridges have multiple layers with different micron sizes. The outer layer has a larger micron size and captures larger particles, allowing smaller particles to pass more profoundly into the cartridge. This design extends the life of the cartridge, increases its surface area, and enhances its sediment-holding capacity.