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Trickle filters offer high quality biological removal of ammonia and nitrite using the same types of media as used in multibay filters. Trickle filtering is about 20% more efficient, and certainly more effective at removing nitrite because the available oxygen remains high throughout the filter. These high concentrations of oxygen are achieved by the water cascading over the media.
If the pond has high stocking and feeding rates, carbon dioxide and hydrogen sulphide concentrations can increase causing the pH to drop. In these circumstances the trickle filter can be used for gas stripping, in which air is blown against the water flow to strip out excess CO2. H2S and N
Filter design and operation

Our Trickle filters follow a simple but very effective design. All filters maintain high flow rates, as there are no internal or external mechanisms to block, jam or fail. Filter maintenance is simple and straight forward. The filter media can be any type of open structure, such as flocor or alfagrog. Media should be contained in a net bag for ease of handling. A media support tray is included with the filter, as is a distribution plate. Pre filtered pond water is pumped into the filter at the top and exits from a low level outlet. This can return directly to the pond or recirculate in the filter.

Use and Application

Trickle filters must be installed above pond water level, they do not have to be adjacent to the pond, but return pipes should be properly sized to accommodate the flow. They can be the only biological filtration on a pond if required, or a useful ' add on ' to an established system which needs supplementing because of additional fish or increased feeding. Our small 'filter top ' range is designed to sit on top of an existing multibay filter, a small submersible pump is used to supply the trickle filter with the overflow returning back into the multibay filter, this allows for significant additional filtration but with a minimal space and installation requirement. Our larger stand alone filters are available, square, rectangular or cylindrical.
All filters are made from industrial grade black embossed polypropylene. Other sizes available to order. Special designs made to order
Filtration Capacity as stated in the following table refers to the live weight of fish in the pond. To estimate the weight of a fish from its length refer to the chart on page 1

Product code	Filter type	Size height first	Media capacity	Filtration capacity	Flow rate Litres/hour	Inlet size	Outlet size
TFR-60-38	Cylinder	0.6m x 38cm	55 Litres	20kg	up to 5000	1½"	2"
TFR-100-38	Cylinder	1.0m x 38cm	63 Litres	22.5kg	up to 5000	1½"	2"
TFR-122-38	Cylinder	1.2m x 38cm	110 Litres	40kg	up to 8000	1½"	2"
TFR-150-61	Cylinder	1.5m x 61cm	380 Litres	135kg	up to 12000	1½"	2"
TFR-150-90	Cylinder	1.5m x 90cm	850 Litres	303kg	up to 30,000	1½"	2"
TF-50-50-25	Rectangular	50 x 50 x 25cm	50 Litres	18kg	up to 5000	1½"	2"
TF-60-60-25	Rectangular	60 x 60 x 25cm	75 Litres	27kg	up to 5000	1½"	2"
TF-60-60-45	Rectangular	60 x 60 x 45cm	135 Litres	50kg	up to 10,000	1½"	2"
TF-100-75-75	Rectangular	1m x 75 x 75cm	325 Litres	116kg	up to 22,000	1½"	2"
TF-200-90-90	Rectangular	2m x 90 x 90cm	1300 Litres	465kg	up to 30,000	1½"	2"

Trickle Filter without Media
Code	Price	Order
TFR-60-38	£
TFR-100-38	£
TFR-122-38	£
TFR-150-61	£
TFR-150-91	£
TF-50-50-25	£
TF-60-60-25	£
TF-60-60-45	£
TF-100-75-75	£
TF-200-90-90	£

Trickle Filter inc. Flocor Media
Code	Price	Order
TFR-60-38M	£
TFR-100-38M	£
TFR-122-38M	£
TFR-150-61M	£
TFR-150-91M	£
TF-50-50-25M	£
TF-60-60-25M	£
TF-60-60-45M	£
TF-100-75-75M	£
TF-200-90-90M	£