Transparent as the water that comes from a source! But where does it come from? How can it be so clean after all the road it has travelled?
It falls on the ground and on the dust, on the streets it has cleaned all the things it has found, it has brought mud and debris, it has disappeared for a while and then returns clean and transparent as it arrived.
When you don’t see it, it infiltrates in the ground, in the beds of streams, rivers and canals, it goes through gravel and sand and it is deposited in the aquifers leaving dirt and debris on the soil, on the gravel and on the sand like a filter!
In this way, the sand filter was created to clean the water, as something that always happens in nature. A system as old as water but that always works!
Technology has reproduced the same process by making water to be cleaned go to a tank full of sand, or better than that, full of quartzite.
It is recommended to use quartzite sand with a grain size of 0.8 – 1.2 mm