In single media filters, the smallest particulate media are dominant due to density awareness. Because the smallest media is at the top, usually the filtration is in the first few centimeters of the media. For this reason, the pressure loss increases rapidly and accelerates the media to enter the reverse wash.

Ideally, the largest particle media should be at the top and the particle or media size must be reduced towards the stream of water. In this way, the mass retention capacity of the media is increased by keeping large particles in the top layer, middle particles in the middle part of the media and smallest particles in the bottom layer. This will require less backwashing

Garnet media is the heaviest media material due to its specific density 4 and can filter to a range of 10 - 20 microns. The filter sand or Türbidex mineral is used as the middle layer and the anthracite medium is used as the top layer mineral with the lowest density and the largest particle size.

Multi - layer filters (multi - media) can be used both in water and in wastewater. Although the amount of media can be changed according to the quality of the raw water and the quality of the treated water, 55% of the filter bed usually consists of low density minerals, 30% of medium density and 15% of high density media.

If heavier filtration minerals are to be used, garnet number 8 acts as an ideal support bed.

 PHYSICAL PROPERTIES

Color: Reddish Pink

Density: 130 - 140 lbs / ft3

Size: 0,35 x 2mm

Specific Weight: 3.8 - 4.2 g / cm3

Uniform Coefficient: 1,3 - 1,5

Silica Content: Minimum

Acid Resolution: Minimum