Evolution Aqua K1 Filter Media – 1L & 3L

Evolution Aqua K1 Filter Media – 1 Litre and 3 Litres

Evolution Aqua K1 is a floating plastic filter medium for compatible biological and mechanical filtration systems. Its small, wheel-shaped pieces provide surfaces for beneficial bacteria to grow, while the open shape allows water to pass through the media. These smaller packs are useful when filling a compact chamber, adding a measured quantity to an existing system or replacing media that has been lost during servicing.

Choose the 1 litre or 3 litre pack from the options. This is standard K1 media: it is a different product from K1 Micro and K+ media. Check the instructions for your filter before choosing, particularly where retaining screens, cleaning arrangements or the specified media volume are designed around a particular type.

Standard K1 specifications

The surface-area figures describe the structure of the media. They are not a pond-volume rating or an instant measure of how many fish a filter will support. Actual biological performance depends on the amount of mature media, feeding load, water conditions, oxygen supply and the design of the complete filter.

How K1 supports biological filtration

The protected surfaces inside each piece provide space for a biofilm to develop. In a working biological filter, this includes bacteria involved in converting ammonia and nitrite. New media needs time to mature; adding a fresh pack does not immediately make a heavily stocked pond safe or replace the need to test the water.

Keep filtration and aeration working consistently while the media establishes. Changes in feeding, fish numbers or temperature can change the load on the filter, so use water-test results to judge how the system is coping. Clear water alone does not tell you whether ammonia and nitrite are under control.

Using K1 in a moving bed

K1 has near-neutral buoyancy and is designed to circulate in a suitably arranged moving-bed chamber. The media needs enough space to move and a suitable air or water flow pattern. Filling a chamber tightly with floating media defeats the purpose of a moving bed; the maximum fill should follow the filter manufacturer’s guidance.

Before adding more K1, check the working media volume already present, the space available and the ability of the aeration system to keep it circulating. A larger quantity of media may require changes to the air distribution. Do not assume that adding more material to an unchanged filter automatically improves its performance.

The chamber also needs suitable media-retaining screens at the inlet, outlet and waste route. Check the size of every opening against the actual K1 pieces so that media cannot escape into pipework or reach a pump. Retaining media safely is especially important in a home-built filter or when changing from a larger type of biological medium.

Static filtration and choosing the correct medium

Some filter designs use K1 in a static arrangement for mechanical filtration. That is a different operating method from an aerated moving bed. Trapped debris must be removed through the filter’s intended cleaning process, and the media should be used only where the filter’s design supports it.

For a system that specifies smaller media, compare Evolution Aqua K1 Micro. Its smaller dimensions affect retention and flow arrangements, so it should not be substituted simply because both products carry the K1 name. If your installation specifies the newer K+ medium, see Evolution Aqua K+ Filter Media instead.

Choosing between the 1 litre and 3 litre packs

The 1 litre pack is convenient for small additions where the required quantity has already been measured. The 3 litre pack supplies three times that volume of the same standard K1 medium. Neither option includes a filter vessel, media basket, air pump or biological starter product.

Use the filter’s stated media requirement to work out the quantity needed. A chamber’s overall volume is not necessarily its allowable media volume: space may be needed for water flow, aeration and cleaning. For an existing filter, subtract the media already in place before ordering a top-up and allow for any manufacturer restrictions on adding more.

Adding media and caring for the filter

Follow the filter manufacturer’s procedure when opening or draining the system. Keep established biological media wet and avoid unnecessary disturbance to the whole biological stage during a small top-up. Check that seals, retaining grids and waste valves are correctly fitted before returning the filter to normal operation.

After restarting, inspect the media movement or static-bed flow as appropriate to the filter. Check that no pieces are escaping and that water levels remain normal. Continue routine maintenance of the mechanical stage so that accumulated solids do not reduce flow through the biological section. Keep a record of the volume added; that makes future servicing and filter adjustments easier to plan.