In a sieve filter the water from the pond is led over a curved sieve. The sieve consists of hundreds of triangular sticks with a spacing of 0.2 or 0.3 mm (also called 200 or 300 microns). The rods are slightly tilted, so that the coarser dirt remains on the sieve and the ‘sieved’ water falls through. The sieved water is led further to the main filter. AquaForte has various sieve filters in its range, such as the CompactSieve, MidiSieve, SmartSieve and UltraSieve.