2 x Microfilter pads + 2 x Filter fleece suitable for e.g. Eheim: Außenfilter prof. 3 1200XL (2080) Thermo Außenf. prof. 1200XLT (2180) beforehand: suitable f. e.g. Eheim-prof. III (2080)
Microfibres highly compressed by a special manufacturing process allow to filter out the finest suspended impurities .It even removes free-floating algae without chemical additives.