Many of you use a carafe filter in your home, and you have questions about how it works.
We will try to answer them, without entering into a scientific debate that is already widely available.
We display at the bottom of this article the links to a very complete study carried out by the ANSES and another carried out by the association “Que choisir”.
A carafe filter is composed of a double tank container, the upper part is made to receive the water to be filtered, the lower part to store the filtered water.
In the middle there is a plastic filter, which should be changed every month or after 100 liters of filtered water.
Here are the contents of the filter of a carafe filter:
The white beads are ion exchange resins, the black beads are activated carbon, all wrapped in plastic, and enriched with silver particles to prevent bacterial growth in the filter.
As for coffee pods, it is very difficult to recycle, except by paying a lot of money for a specific process, because of the mix of components, and the low value of materials.
The water that you pour into the top tank of the carafe filter will pass by gravity through these balls (it takes several minutes and it must be done in several times) into the bottom tank. The filter jugs are not airtight and therefore require some precautions for their use / storage.
It is also important to understand that the useful capacity is not the advertised one, but only the one of the low tank: the advertised capacity of 2.4 liters for the most common models contains only 1.4 liters, but rather occupies a good 3 liters of volume in your refrigerator, which usually does not have a dedicated carafe filtering place.
Let’s talk about trace elements and filtering carafes
But let’s talk about trace elements, and more specifically calcium and magnesium.
A carafe filter strongly reduces the calcium, about 80 to 90% thanks to the white resin beads, it is a fact in their leaflet.
Calcium and magnesium are however essential to our good health, and certainly not responsible for kidney stones. We buy mineral water at 30 cents a bottle for its calcium and magnesium content, or cheese, or milk, why not drink the one that comes to us?
In addition, to reduce calcium, these products replace it with sodium, resulting in saltier water at the outlet. So be careful if you have excess salt in your body or a particular diet to follow.
So, yes, it is a fact that a carafe filter also reduces chlorine in the same proportions, and this is probably the first reason for its use.
But, according to Ances, it produces acidic water, the pH goes from 7.5 to 6, and becomes corrosive to metals. In fact, a spoonful of citric acid will effectively clean the limescale for 2€ per kg, but in reality, you won’t put back the corroded metal of your kettle, which will corrode and then break through if you boil it with acidic and salty water too often. Therefore, it is not recommended to use filtered water in household appliances that heat water in metal: kettles, coffee machines, etc..
An alternative to the carafe filter… without filter!
LaVie® UV-A water purifiers operate without filters or maintenance and allow you to purify your tap water in 15 minutes.
They use an innovative, patented technology exclusive to LaVie®: the photolysis of chlorine by UV-A radiation.
This treatment allows the removal of chlorine and its by-products, chemical compounds such as certain pesticides or traces of medication, tastes and odors that can be found in tap water.
The result, very qualitative, allows to draw a definitive line on the consumption of plastic bottled water.
The carbon footprint associated with the manufacture of the UV water purifier’s aluminum tube is neutralized in a few days of use compared to the equivalent consumption of water in plastic bottles.
What about the bacteria in the filter jugs?
The last point is bacteriological. The UFC que choisir and the ANSES warn after analysis on “nests of bacteria” measured in the daily use of filtering carafes.
With this information, you can choose your water purifier with precision, according to your needs and uses.