Of all the hundreds of different types of pond filter available, they all fall into basic categories, In-pond, Flow-through or pressure filters.
In this section we will look into the simple forms of filtration available for the garden pond. More complex articles will follow covering Koi filtration in a number of different forms.
Flow through filters
The key is in the name: A flow-through filter is fed by the pump sitting in the pond. The filter is the highest point in this cleaning cycle; from this point the water then flows back into the pond. Foams in the interior perform the actual cleaning of the water; after a few days these foams also become the home for the hard working microorganisms. The advantage of flow-through filters: They are easy to reach, they are above ground, thus cleaning and maintenance are quickly accomplished. There are many innovative products in the OASE product range. Systems with self-cleaning function, such as the FiltoMatic or the Screenmatic prefilter spare you endless hours of pond cleaning. Thus there is more opportunity to enjoy your leisure time and relax at the edge of the pond.
As opposed to flow-through filters, pressure filters route the pump pressure through the filter. They can also be used below the surface level of the water. Consequently they are used classically for higher positioned watercourses; they can be partially buried in the ground adjacent to the watercourse where they do not disturb the natural garden look. This makes the closed system of the filter possible, which is ensured by the quick-release closure. Ideally inflow hose and outflow hose are routed through the pond liner with the Tradux system. The cleaning processes function in accordance with the same principle as that of the flow-through filter and consequently also offer, (with correctly matched pond and filter size), a good basis for optimally filtered water. A number of pressure filters offer a cleaning facility that you can perform without tacking the lid off the unit. Both Oase Biopress and Oase filtoclear units can be cleaned in this manner as Oase like a number of other reputable manufacturers have realised that regular maintenance is the key, a small amount of maintenance on a regular basis goes a long way to ensuring a stable pond environment.