Kaldnes Moving Bed process, which has been scientifically tried and tested in fish farming and waste water treatment for over 10 years, is now available for fish keepers and is exclusively distributed worldwide by Evolution Aqua.

The media is engineered in a wheel shape and is slightly positively bouyant. This allows a small amount of water flow to circulate the media throughout the vessel. This flow is created with your air pump and air stones or diffuser etc.

How it works

Maturing the Kaldnes bio-media is important because a delicate eco-system is naturally developing for the bacteria involved in the nitrification process. Kaldnes media provides the maximum active surface area for the bacteria to colonise, more than other types of static media. It is this process which removes harmful ammonia and nitrite from the water.

How it is different to other media

As the Kaldnes media moves within the filter, it causes the old dead bacteria on the outside to be displaced. This makes space for new younger heavier feeding bacteria to rapidly colonise. Within the wheel is a protected surface which enables colonies of bacteria to naturally follow their lifecycle, of maturing, dying and then fueling the latter stages of the nitrification cycle. Kaldnes has been designed to provide the best possible habitat for both young and mature beneficial bacterial colonies.

What is meant by 'self cleaning'?

Unlike foam, matting, or other forms of static filtration media, the Kaldnes K1/K3 media is designed to move freely within your filter. The constant chaotic movement of the air from your pump, causes the media to self clean and thus requires no maintenance. This allows the filter to reach optimum effectiveness without the disturbance of periodic cleaning, avoiding unnecessary loss of bacteria within the filter. 50 Litres of K1 media will handle up to 250 grammes of food per day and for K3, 225 grammes of food per day. For retrofit of existing filters, K3 media is the most suitable due to its larger size and ease of control.

The Cetus sieve is a totally new, bow screen pre-filter, made using the latest rotational molding technology. With all of its benefits and build quality, it is undoubtedly the best of its kind on the market today, regarding quality and performance! It is designed to efficiently and effectively remove large amounts of mechanical waste from a pond. It can be set-up gravity OR pump fed and has many benefits over the original bow screen technology.
This Cetus has a variable inlet height using the unique patented Pondflow regulation system – for use when gravity fed. This allows water levels within the pond to drop without causing the circulating pump to be starved of water. The Cetus will allow a skimmer or a bottom drain to accept vast amounts of waste without excessive cleaning needed to be carried out. The water must then be pumped to either a normal filter above pond level (Nexus Eazy/Eazy Pod) or to a pressurised filter.
If pump fed, the sieve is placed above pond water level and then the exit water is gravity dropped into your main filter.The Cetus sieve is a bow screen pre-filter, suitable for pre-filtration of any biological filter including all pressured filters. It is advised that all pressurised filters be pre-filtered using a Cetus to reduce excessive backwashing and maintenance due to heavy solids.
Can be gravity OR pump fedPerfect fit screen so no waste can bypassTotally reliable and simple to installPlug and Play – comes with flexible boots toconnect to pipe workGreatly reduced backwashing / maintenanceof pressurised filtersRobust one piece mould –no welded joints – no leaks!Large waste collection area which slopes to sump outletIdeal for mechanically filtering skimmer linesPatented float that gives constant flow forgravity-fed level fluctuationsMaximum flow rate 18,000 litres per hourTri-slot 300 micron wedge wire screen in 316Lstainless steel on 100% of surface areaIncreased levels of oxygen

The Cetus sieve is a totally new, bow screen pre-filter, made using the latest rotational molding technology. With all of its benefits and build quality, it is undoubtedly the best of its kind on the market today, regarding quality and performance! It is designed to efficiently and effectively remove large amounts of mechanical waste from a pond. It can be set-up gravity OR pump fed and has many benefits over the original bow screen technology.
This Cetus has a variable inlet height using the unique patented Pondflow regulation system – for use when gravity fed. This allows water levels within the pond to drop without causing the circulating pump to be starved of water. The Cetus will allow a skimmer or a bottom drain to accept vast amounts of waste without excessive cleaning needed to be carried out. The water must then be pumped to either a normal filter above pond level (Nexus Eazy/Eazy Pod) or to a pressurised filter.
If pump fed, the sieve is placed above pond water level and then the exit water is gravity dropped into your main filter.The Cetus sieve is a bow screen pre-filter, suitable for pre-filtration of any biological filter including all pressured filters. It is advised that all pressurised filters be pre-filtered using a Cetus to reduce excessive backwashing and maintenance due to heavy solids.
Can be gravity OR pump fedPerfect fit screen so no waste can bypassTotally reliable and simple to installPlug and Play – comes with flexible boots toconnect to pipe workGreatly reduced backwashing / maintenanceof pressurised filtersRobust one piece mould –no welded joints – no leaks!Large waste collection area which slopes to sump outletIdeal for mechanically filtering skimmer linesPatented float that gives constant flow forgravity-fed level fluctuationsMaximum flow rate 18,000 litres per hourTri-slot 300 micron wedge wire screen in 316Lstainless steel on 100% of surface areaIncreased levels of oxygen

The Nexus 210/310, Evolution Aqua's world leading filtration system has now got better. Incorporating the industry proven Kaldnes Moving Bed coupled with the exceptional New Eazy mechanical filter. Combined they provide outstanding water clarity and quality. It is extremely 'Eazy' and pleasurable to clean.
The Nexus 210/310 is a cleverly combined mechanical and biological filter creating an effective, high performance filtration system for all sizes of pond. It has and continues to revolutionise the way ponds are filtered. The Nexus combined with the New Eazy, means there really is no competition regarding price and what it will achieve.

The Nexus 210 is rated for 4500 gallons.

The Nexus 210/310, Evolution Aqua's world leading filtration system has now got better. Incorporating the industry proven Kaldnes Moving Bed coupled with the exceptional New Eazy mechanical filter. Combined they provide outstanding water clarity and quality. It is extremely 'Eazy' and pleasurable to clean.
The Nexus 210/310 is a cleverly combined mechanical and biological filter creating an effective, high performance filtration system for all sizes of pond. It has and continues to revolutionise the way ponds are filtered. The Nexus combined with the New Eazy, means there really is no competition regarding price and what it will achieve.

The nexus 310 is rated for 7500gallons.