Are More Stages Better in a Filtration System?

The number of stages in reverse osmosis filtration (RO) has become industry jargon for demonstrating filtration superiority, or water quality. Is this indeed the case? Could it be a marketing ploy to get you to buy extra features or add-ons that you don’t need? Here is our take on the age-old matter of having more stages in a filtration system.

What Does Each Stage of a Reverse Osmosis Filtration System Do?

A basic RO system has three distinct filter stages: sediment filtration, carbon filtration, and reverse osmosis. Each filtration stage is vital, and they work together to provide the greatest water filtration possible.

Sediment filtration eliminates dust, silt, particles, and rust from water. Sediments are usually used in the initial stage of filtration to help remove or trap larger particles so that subsequent stages can focus on trapping contaminants that sediment filtration can’t.

The following phase is carbon filtration, which absorbs tastes, odors, cloudiness, colors, and other chemicals such as volatile organic compounds (VOCs) before the water moves on to the next stage. Some VOCs include chlorine and chloramines.

The final stage of the filtration process, reverse osmosis, is also the heart of the entire system. Water is pumped through a semipermeable membrane with a rated pore size of 0.0001 microns. Contaminants such as lead, arsenic, and nitrates are eliminated from the water to the tune of 99 percent.

Why Do We Add More Stages After Reverse Osmosis?

Reverse osmosis water is sometimes described as flavorless water, which many people are unfamiliar with. Adding a coconut shell carbon filter to the water helps remove the leftover flavor while also adding some sweetness. A remineralization filter is included in certain reverse osmosis systems to help restore the mineral taste.

How Many Stages Are Needed for Reverse Osmosis Filtration?

The reverse osmosis stage alone is required to eliminate all water impurities. However, as previously stated, the processes prior to it eliminate all of the larger impurities so that reverse osmosis can work more efficiently and last longer. After that, stages assist in improving the taste. From a cost and performance standpoint, four stages are ideal: sediment filtration, carbon filtering, reverse osmosis, and a post-taste refining filter.

Hopefully, you now understand if it’s better to have more stages in your filtration system. After all, there’s no use in two layers of carbon filters if they’re both employing the same sort of filtering. So, when you’re ready to acquire an under counter filter system for your home, be sure you understand exactly what you’re getting, and if you actually need it.