THE spigot in the laboratory of Pontianak Good Shepherd Catholic Senior High School does not at first glance inspire a second look. Like any other faucet, when the tap is turned, water flows out.

But tucked away inside a tube connecting the spigot to the wall, is a hidden container filled with black powder. This is where the magic happens.

The black powder is a new kind of filtration system; one that removes harmful heavy metals from water.

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