The effective size of the sand particles used in the top layer of slow sand filter is in the range of:
1
0.45 to 0.70 mm
2
0.40 to 0.60 mm
3
0.20 to 0.30 mm
4
0.35 to 0.55 mm
The effective size of the sand particles used in the top layer of slow sand filter is in the range of: