3 ms·
New as in 200 years old technology: https://en.wikipedia.org/wiki/Slow_sand_filter https://en.wikipedia.org/wiki/Slow_sand_filter
by ahoka 5y ago
New as in 200 years old technology: https://en.wikipedia.org/wiki/Slow_sand_filter https://en.wikipedia.org/wiki/Slow_sand_filter
- kamray23 5y agoNew as in a new strain of algae useful for weeding out specific man-made forms of pollution. Also applying it to wastewater.