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Evolution Aqua

Evolution Aqua K+ Media

Bag Size





Plastic media, for use in biological Pond filters - specifically in moving bed bio reactors, was pioneered by Evolution Aqua, some 20 years ago. In recent years, other plastic media have come onto the market, usually with the aim of trying to get more and more surface area.  However, one drawback to using plastic media has always been the time it takes to establish a stable biofilm – essential for good filtration.

After many years of research, Evolution Aquahave now developed a new media that not only gives class leading surface area, but also overcomes the problem of long maturation times.


K+Media is designed and manufactured in the UKby Evolution Aqua. This advanced media, with its innovative design, and class leading surface area provides enhanced biological and mechanical filtration.

As Evolution Aqua extrude the K+Media, Minerals and Enzymes are added to the raw material.  The result of this process, unique to Evolution Aqua, is a filtration media that not only outperforms most of its competitors due to its large protected surface area, but also answers the problem of how to speed up the time taken to mature your filter.



Class leading total surface area 1,350m2 per m3

■ Vast protected surface area 1,025m2 per m3


Filters mature faster with K+Media


Minerals, magnesium, calcium, salt and enzymes incorporated into the K+Media during    the extrusion process

Design and structure of K+Media allows a stable bio-film to form

Microscopic organisms such as Rotifers and Vorticella thrive in “quiet zones”

Exceptional solids removal thanks to efficient, proven design

Reduced energy consumption, less back pressure on pumps

■ Used in Nexus+ filters for improved biological filtration in moving bed

■ Available as floating or sinking versions in 25 litre or 50 litre bags







During the extrusion process, Evolution Aqua add a range of minerals, along with magnesium, calcium, enzymes and salt to the raw material that is used to manufacture K+Media.  The result means that K+Media will mature much faster than many other types of media.


  • The addition of these minerals creates a rough surface on the media. This textured surface has a microscopic honeycomb of peaks and craters that allow waste particles to collect, and nitrifying bacteria to form.


  • The minerals act as a food source for the bacteria, helping the bacteria to develop and multiply at a faster rate, further improving maturation times.


  • Calcium alone has proven advantages for developing and maintaining effective bio-films.


  • The enzymes that are added also help to make the media “sticky” so waste particles can adhere to media easier.


  • Salt is added during the extrusion process, which is dissolved during the cooling process, leaving a rough surface on which bio-film can easily adhere.





With a new shape and profile, K+Media has also been designed to have an increasedand class leading surface area, meaning an overall surface area of 1,350m2 per m3. More importantly for biological filtration, the protected surface area of K+Media is 1,025m2 per m3.  This allows a stable bio-film to form and remain intact when used in moving bed biological filtration, as in the new Nexus+.




The shape of K+Media optimises the amount of “quiet zones” within the media where a stable bio-film can develop. Whilst K+Media keeps the integral profile of K1 Media at its core, there is an extra layer of cells and fins around the outside of each piece that enable microscopic organisms such as Rotifers and Vorticella to thrive. This is an additional benefit as competitor media do not have such “quiet zones” that would allow these higher lifeforms of filter feeders to develop. The bacteria and organisms that form within the bio-film ensure the media delivers optimum levels of biological filtration in the moving bed, which has been proven filtration technology for many years in the fishkeeping hobby.







Diameter =10.2mm

Total surface area =1,350m2 per m3

Protected surface area =1,025m2 per m3

Length =8mm


Available in bags of 25 litres and 50 litres

Floating version is coloured white

Sinking version is coloured black

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