A filter system for filtering suspended particles from a liquid, said filter system comprising: a housing having an inlet for receiving liquid, and an outlet for enabling liquid to leave said housing; a first filter device (16a, 116a) arranged within said housing between said inlet and said outlet, said first filter device comprising a first synthetic low friction surface layer; said first synthetic low friction surface layer comprising a plurality of pores having a first pore size allowing suspended particles of a size smaller than said first pore size to pass through said first synthetic low friction surface layer together with the liquid; wherein said first synthetic low friction surface layer prevents a majority of the suspended particles of a size larger than said first pore size to attach to said first filter device; wherein said first synthetic low friction surface layer has been subject to thermal treatment, plasma treatment, or silicon based plasma treatment wherein said filter system further comprises: a second filter device (16b, 116b) arranged upstream of said first filter device, said second filter device comprising a second synthetic low friction surface layer having a plurality of pores having a second pore size allowing suspended particles of a size smaller than said second pore size to pass through said second synthetic low friction surface layer together with the liquid, wherein said second pore size of said second synthetic low friction surface layer is larger than said first pore size of said first synthetic low friction surface layer; and wherein said second synthetic low friction surface layer of said second filter device in said filter system comprises a hydrophobic layer and said first synthetic low friction layer of said first filter device comprises a hydrophilic layer such that said hydrophobic layer is located upstream of said hydrophilic layer. a housing having an inlet for receiving liquid, and an outlet for enabling liquid to leave said housing; a first filter device (16a, 116a) arranged within said housing between said inlet and said outlet, said first filter device comprising a first synthetic low friction surface layer; said first synthetic low friction surface layer comprising a plurality of pores having a first pore size allowing suspended particles of a size smaller than said first pore size to pass through said first synthetic low friction surface layer together with the liquid; wherein said first synthetic low friction surface layer prevents a majority of the suspended particles of a size larger than said first pore size to attach to said first filter device; wherein said first synthetic low friction surface layer has been subject to thermal treatment, plasma treatment, or silicon based plasma treatment wherein said filter system further comprises: a second filter device (16b, 116b) arranged upstream of said first filter device, said second filter device comprising a second synthetic low friction surface layer having a plurality of pores having a second pore size allowing suspended particles of a size smaller than said second pore size to pass through said second synthetic low friction surface layer together with the liquid, wherein said second pore size of said second synthetic low friction surface layer is larger than said first pore size of said first synthetic low friction surface layer; and wherein said second synthetic low friction surface layer of said second filter device in said filter system comprises a hydrophobic layer and said first synthetic low friction layer of said first filter device comprises a hydrophilic layer such that said hydrophobic layer is located upstream of said hydrophilic layer. a second filter device (16b, 116b) arranged upstream of said first filter device, said second filter device comprising a second synthetic low friction surface layer having a plurality of pores having a second pore size allowing suspended particles of a size smaller than said second pore size to pass through said second synthetic low friction surface layer together with the liquid, wherein said second pore size of said second synthetic low friction surface layer is larger than said first pore size of said first synthetic low friction surface layer; and wherein said second synthetic low friction surface layer of said second filter device in said filter system comprises a hydrophobic layer and said first synthetic low friction layer of said first filter device comprises a hydrophilic layer such that said hydrophobic layer is located upstream of said hydrophilic layer.