Maintaining a healthy pond environment with crystal clear water usually requires some kind of filtration system. Filtration systems can perform one or many of the following functions:
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Mechanical filtration - Particles are trapped in some type of medium for removal during the cleaning. - Biological filtration - beneficial bacteria feed on impurities in the water, breaking down fish waste and other organic matter. - U.V. Clarification - water is exposed to ultraviolet light, making the particles in the water clump together for removal by mechanical filtration |
Most
filters for mid-sized to large ponds employ a combination of mechanical
and biological filtration. They can often accommodate an ultraviolet
clarifier as an option. Cyprio, a pioneer in filtration systems for
garden ponds, offers a wide range of filtration systems, all of which
combine mechanical and biological filtration. Depending on the brand
and model, the mechanical filtration can consist of
(1) Layers of foam pads
(2) Trays of gravel
(3) Foam Cartridges, or
(4) Brushes.
Some models combine many of these features in one unit.
In addition many of these filters contain a chamber of plastic 'bio-media'. These specially designed pieces of plastic have an extremely high surface area to encourage the growth of colonies of beneficial bacteria, the secret to effective biological filtration.
Once the colony of bacteria is established, it converts ammonia from fish waste and dead organic matter first into nitrites and later into harmless nitrates and nitrogen, which help promote the growth of your plants.
Without help it can take as much as seven weeks for a bacteria colony to grow large enough to be effective. However, colony growth can be accelerated by adding beneficial bacteria available in dry, granular, or liquid form.
The rate of water flow through the biofilter will have a major impact on it's effectiveness. Faster water flow may not allow the bacteria to adequately clean the water and may actually dislodge the bacteria from the filter media.
Care should be taken when cleaning a biofilter. Mechanical elements should be rinsed in a separate container of pond water. The biomedia should be disturbed as little as possible to enable the beneficial bacteria to remain. Filter designs differ depending on their planned placement. Some small filters are designed for underwater use, usually near a submersible pump. Others, like Cyprio's Biofloc and Gravity Green Machine, are designed for in ground use.
In the case of in ground filters, the lid of the filter is above the ground for easy access, yet the filtration media is situated below the water level, often concealed underground. Yet others are intended for above ground use. Examples of above ground units include Cyprio's Biozorb, and Classic Green Machine.
Filter
Size:
Selecting
a filter for your pond based on volume alone is not enough. You must calculate
the 'effective volume' of your pond, which is influenced by many environmental
factors.
Determine if your pond is affected by direct exposure to sunlight, shallow depth, or climate conditions, and add to the total volume using the factors listed below.
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Average pond depth less than 2 feet 6 inches deep - add 25% - Pond located in full sunshine - add 25% - Climate (1) Subtropical - add 35% (2) Temperate - add 15 % (3) Northern - No effect - Fish stock level should not exceed 10 inches per 100 gallons of filtration. |