FRP pretreatment tank can be divided into filter tank and softening tank according to use. The filter tank can be divided into mechanical filter tank, multi-media filter tank, activated carbon filter tank, iron and manganese filter tank and so on according to the different filter material filled.

1. Mechanical filter tank: The pressure filter is used in the pre-treatment system with well water or tap water as the water source.

2. Multi-media filter tank: The use of a variety of filtration media, under a certain pressure to the higher turbidity of the water through a certain thickness of the filter layer, so as to effectively remove the water is very small colloidal particles and suspended matter, water erosion reached about 1 degree.

3. Activated carbon filter tank: granular activated carbon or synthetic large pore adsorbent, adsorbed carbon, etc., are used as filter media. It is characterized by wide application range, good treatment effect, small footprint, reliable operation, convenient management and renewable adsorbent. Can be made into gravity or pressure adsorption column alone. Activated carbon filter can remove organic matter, colloidal particles, microorganisms, residual chlorine, odor and so on.

4. Remove iron and manganese filter tank: used to deal with groundwater or well water with high iron and manganese content, filled with manganese sand filter material, the use of water in full contact with oxygen and through the catalysis of manganese sand, the iron and manganese oxidation in the water, forming colloidal precipitation.