K1 media has been used by Evolution Aqua in Koi filtration systems for a number of years. This new type of filter media, K1 Micro, contains all of the benefits of traditional K1 media but is extruded in a much smaller form. The small wheel shaped filter media pieces provide a significantly increased protected surface area per cubic metre when compared to standard K1 for bacteria to colonise. This makes K1 Micro an ideal filter media for aquariums of all types where high level biological filtration is needed. K1 Micro can also be used to replace existing filter media.