We made several tests to confirm or discover the role of the components within the filter:

The main test is to see if we can have "drinkable" water from a very salty water. We used the sand, carbon filter and a basic filter like a coffee filter.

After many try, we reached to some conclusions witch are:

the sand is filtering the salty but it's not very effective but it has the advantage to clear the water

the carbon is filtering the salt more than the sand but the water taste a bit weird after being filtred

The coffee filter is only useful to contain the sand and the carbon from being in the water

To conclude to two filter are complimentary to filter the salt and clear the water but the result after only one filtering is not very effective but with multiples filtering we can feel at the taste and from visual that the filter is working (in a restricted manner)

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