What is triple filtered water?

There are lots of water filters on the market and each filter has unique features that separate it from the rest. While most people are satisfied with a water pitcher featuring a single filter, others are more cautious and go for a filter that promises triple filtered water.

Some filters add some more stages to the initial three-stage filtration process to end up with a 4-stage, 5-stage, 6-stage, 7-stage, or even 8-stage filtered water. But for the most part, the 3-stage filtered water is good enough. In fact, Starbucks uses a 3-stage RO system to purify their water and this is believed to be the secret behind their water tasting so darn good.

The stages of triple filtered water explained

  • Stage 1: Stage one uses a 20” filter to eliminate particulate matter like silt, rust, and dirt from the water. Such sediment can affect the taste of water if not removed. Besides, removing the sediment at this stage also helps to protect the carbon filter that is used at the later stages.
  • Stage 2: Stage two uses activated carbon to eliminate chloramines and chlorine from the water as a way of preparing the water for the actual reverse osmosis stage. Stage two also improves the taste of water while at the same time protecting the reverse osmosis membrane from degradation.
  • Stage 3: This is the final stage of the 3-stage reverse osmosis filtration system and this is where the actual reverse osmosis takes place. It utilizes an RO membrane to eliminate inorganic and organic compounds (e.g., fluorides, lead, arsenic, copper, etc.) After the water is taken through this third stage, the TDS will be reduced to almost 0.0001 of a micron and this is why reverse osmosis systems are said to eliminate 99.99% of impurities in water.

The overall effect is water that is free from impurities and has great taste too. Establishments like Starbucks use a three-stage filtration system to filter their water and that explains why patrons just can’t have enough of the Starbucks water.

What is the best 3-stage RO system?

APEC 3-stage RO system (amazon link) is our top pick. Unlike some of its competitors on the market, it is not only designed but also engineered and assembled in America. As a consequence, this 3-stage RO system uses USA-made cartridges that use food-grade calcium from trusted sources. The filters are durable and you are guaranteed the removal of 99% of impurities.

What are the stages in a 7-stage filtration system

Some RO systems have improved on the 3-stage filtration process by adding some additional stages to give even better-quality drinking water. These are the stages that water goes through in a 7-stage RO system;

  • Stage 1 – This stage is also referred to as a pre-sediment filtration stage and it targets the removal of any visible impurities in water. While this stage may not be necessary with tap water, there are some scenarios where it can be very handy e.g., rainwater, well water, etc.
  • Stage 2 – stage 2 is also referred to as the sediment filtration stage. At this stage, any small sediments that were not captured at the first stage are filtered out. Examples of sediments that might be removed at stage 2 include dust and clay particles.
  • Stage 3 – the third stage is the pre-carbon filtration stage. At this stage, any lead, pesticides, chlorine as well as all other heavy metals are filtered out. Because stage 3 removes heavy metals and chemicals, it also by extension deals with any bad odors in the water.
  • Stage 4 – this is the reverse osmosis stage. The main contaminants that are targeted at this stage are bacteria and other microorganisms. Additionally, any chemicals, salts, and other suspended particles that are still in the water will also be filtered out.
  • Stage 5 – The fifth stage is the UV chamber and just as the name suggests, it utilizes UV light to kill bacteria. So, any bacteria that might have escaped the 4th stage will be killed in the UV chamber.
  • Stage 6 – the sixth stage is also referred to as the post-carbon silver purification stage.  This stage is a backup of the RO stage to eliminate any germs that might still be in the water. That way, even if the RO stage fails, you can still be sure of pure water. This stage also helps to add taste to the water.
  • Stage 7 – This stage is also referred to as the post-carbon silver purification stage. This stage helps to remove pyrogen, colloids, and any other left-over germs in the water.

What is the best 7-stage RO system?

The iSpring 7-stage RO system (amazon link) is our top pick. It removes up to 1,000 different contaminants and therefore gives you pure and safe water for drinking. It is perfect for installing in your home as it comes with easy-to-follow DIY instructions with telephone support in case you get stuck somewhere. It also has a European-Style nickel faucet so your water will not be contaminated with lead or rust.


A 3-stage RO system is good enough for most people because the 3 stages described above are enough to guarantee the removal of 99% of contaminants in water. However, if you have a little bit more to spend, you can go for the 7-stage RO system which introduces some other steps in the filtration process to give you even better-quality water.