6. Pond Filtration: The Balanced Pond

The balanced pond is every water gardener’s dream. The balanced pond ecosystem is a delicate interaction among nutrient levels and the plants and animals that produce and utilize these nutrients. Likewise, this makes pond filtration one of the most important aspects of pond maintenance. Excessive nutrients are caused by over-fertilization and over-population of fish and results in unsightly and unhealthy water.

These problems are avoided with proper planning and sensible filtration. Water gardening is like any other form of gardening – it is just as much an art as a science. Many excellent products and filters are available to help water gardeners be more successful at keeping healthy, thriving plants and fish. Above all, it is possible to achieve a balanced pond with no filtration and nothing more than that perfect mix of plants, animals, and care. But, this is the exception rather than the rule.

Why add pond filtration?

By following a few basic guidelines and by utilizing the most advanced state of the art products, from day one, the beginner can be much happier and successful. For those of you who have already started and been frustrated, it isn’t very hard to change that pea soup mess into something that will add to the beauty and value of your home and give you many hours of enjoyment. Filtration is a very important aspect of pond keeping and makes pond maintenance much easier. It prevents cloud water, while aiding in the success in keeping a larger population of fish.

Types of Pond Filtration

Natural filtration

Although all forms of filtration are somewhat natural, the filtration we refer to here is plant filtration. Plant filtration is the heart of bog gardens. Plant filtration is very important to the balanced pond. First, plants convert carbon dioxide wastes to oxygen. Secondly, plants perform a supplemental type of filtration. In heavily loaded fish ponds, plants help keep abundant fish nutrient waste in check and increase the efficiency of the system.

In systems with large Koi, a small header pond containing either a balanced pond setup of plants or simply submerged plants and nutrient absorbing plants, like water lettuce or water hyacinth, makes an excellent natural filtration system. The header pond or plant filter is fed by a pump and filters from the upper pond which, in turn, drains into the lower pond.

TIP: Add submerged plants in all systems. They are barely visible and are one of the most valuable assets to proper pond balance and filtration. Use 6-10 stems per square foot of pond surface.

See Bog Gardens
See Pond Plants

Mechanical filtration

This form of filtration is exactly what the name implies. It removes particles by straining them from the water onto a medium which can be removed from the system. This is one form of filtration that is incorporated into all good filtration systems. Mechanical filtration also is important before fountain discharges to remove silt and other debris. Using filters on the inlet side of the pump achieves mechanical filtration. Using external filters can work, as well. Well designed external filters of the trickle type or flow-through type incorporate an easily cleaned pre-filter.

Savio white filter pad offers a mechanical filtration solution that works for most ponds. The pad is durable enough to be rinsed and reused several times during a season, but it is economical enough that it can be replaced when necessary. Its porosity allows water to flow through while effectively filtering out particles and debris. 
Savio Filter Pad

This filter media pad offers a mechanical filtration solution that can work for any pond! Available in two sizes, it can easily be cut to fit any filter. This material is made to our specifications for biological and heavy mechanical filtration, and is specifically designed for larger pond filters. It is durable enough to be rinsed and reused several times during a season. Its porosity will allow water to flow through while still effectively filtering out particles and debris.
Green Coarse Filter Media 24″ x 24″ x 2″
Green Coarse Filter Media 36″ x 36″ x 2″

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Biological filtration

This method relies on the biological activity of bacteria to remove pollutants. These bacteria utilize fish and animal waste and turn it into plant nutrients. Biological filtration occurs naturally in the pond on all surfaces. It has increased efficiency with advanced trickle filters. These filters result in water quality far superior to any other form of biological filtration.
OASE ProfiClear Premium Compact-M

BioTec ScreenMatic

• Successfully redesigned high-performance filter
• New foam distribution and optimized water level in the container ensure longer filter service life and an improved cleaning result
• Double-sealed motor and reinforced strap material for an extended service life Lids of models 18000 and 24000 with storm-safe fastening clips
• Cleaning of filter foams directly in the filter, without removal

OA145  BioTec ScreenMatic 18000 suitable for ponds up to 18,000 gallons
OA146  BioTec ScreenMatic 24000 suitable for ponds up to 24,000 gallons
OA147  BioTec ScreenMatic 38000 suitable for ponds up to 38,000 gallons

Chemical filtration

As the name implies, chemical products like activated carbon, zeolites, and resins actually bind certain pollutants for the removal from the water. This form of filtration is important for removing proteins, pesticides, metals, medications and other natural and man-made pollutants. These can disrupt your pond and kill your livestock.

• Premium granular carbon lasts longer, performs better
• Phosphate free
• Keeps fish and invertebrates healthy and active
• Absorbs harmful chemicals, organic compounds, metals, and proteins
• Removes odors and unnatural colors
• Keeps water sparkling clean
• Activation process creates enormous surface area
• Removes pollutants that mechanical and chemical filtration leave behind
• Can be used between filter floss, pads, inside filter bags, or in canister filters
Premium Pelleted Carbon
Treats up to 1600 Gallons .75 Gallons

Media bags prevent media from entering your pump, and keep your pond clean! The fine mesh size effectively holds even small particle carbon and phosphate remover in place while allowing free flow of water throughout the unit for maximum filtration. This media bag easily holds 1000ml of media with room to spare. You can say goodbye to the hassle of ties and strings; this bag features an easy to use zipper that is completely corrosion resistant. Durable and effective, this filter bag can be used over and again.
AL850 Zipper Media Bags 5″ x 10″ – 2 pack
AL173 Zipper Media Bags 10.5″ x 12″ – 1 pack
AL174 Zipper Media Bags 10.5″ x 12″ – 5 pack

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