OASE Pond Filters, Fish & Koi Ponds | Water Garden Ltd
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OASE Pond Filtration & Filter Sets

OASE Pond Filters

Pond filters and pumps play a vital role in maintaining the ecological balance in garden ponds and water features by removing debris and tackling algae growth. Water Garden specialise in German engineered OASE pond filters due to their proven reliability and market-leading technology. Fish pond filters cater for the extra demands placed on the water body due to the nutrients produced by the introduction of food and its consumption. Specialist OASE Koi pond filters are developed to handle and process far greater quantities of waste produced by the larger Koi Carp varieties, whilst maintaining crystal clear water quality.

What is a Pond Filter?

OASE pond filter systems usually consist of 3 primary components:

1.        A solids-handling pump is used, generally submersed directly in the pond or dry mounted.  The purpose of the pump is to pass water and suspended debris to the pond filter for processing.  It’s important that the pump can handle larger solid waste, otherwise this will simply block up with detritus and the filter cannot operate effectively.  The pump will then pass the debris via a flexible hose or pipework to a filter.

2.       An Ultraviolet Clarifier is usually the next step in the process and is designed to emit UV radiation contained safely  inside the UV housing, which causes microscopic organisms such as suspended algae to be killed and flocculated (clumped together).  Single celled algae are individual organisms and without the benefit of a UV Clarifier, would simply pass straight through the filter foams and return back to the pond.  The larger clumps of algae are then passed into the mechanical and biological stages of the filter system for removal and biological breakdown.

3.       The filter, in most cases, contains porous filter sponges of differing pore sizes which are used to mechanically trap the flocculated algae and pond sediment, therefore straining out unwanted pond waste.  The sponges also act as biological housing for beneficial ‘friendly’ bacteria, which help to break down organic matter and otherwise harmful pathogens.  The cleaned and processed water can then be passed back to the pond.

Pond filters are generally left to operate 24 hours a day to constantly process the water.  Switching off the filter pump for prolonged periods will cause the beneficial bacteria to die due to lack of oxygenated water flow.  As the pump and filter are running continuously, it’s important to use the most energy efficient filtration equipment for the task in hand, something which OASE and Water Garden Ltd take fully on board.

Why do I need a pond filter?

Pond filters play a crucial role in helping to keep your pond and its inhabitants clean and healthy.  Whether you own an ornamental, fish stocked or Koi stocked pond, it is important to maintain healthy water quality.  Whilst planting may assist in reducing nutrients, it would be necessary to introduce copious amounts of planting to maintain the ecological balance and this, in many cases, is undesirable or unachievable.  A pond filter will help to tackle single celled algae growth (green water), extract debris and break down harmful nutrients, helping to achieve clear water in ponds and water features alike.

Why are there so many types?

Pond designs vary in many ways so it is important to use the most efficient filter for the specific pond in question.  Pond inhabitants such as goldfish and Koi Carp will also place biological load on the pond, compared to a purely ornamental pond with no fish stock, so filtration needs to be scaled up to cope with this extra load.  As a general rule, a pond which contains small goldfish, shubunkins, Orfe, Comets or Rudd will put twice the strain on fish pond filters compared to no stock.   A pond stocked with Koi Carp will need 4 times the filtration capacity to an ornamental pond with no fish.  Almost all OASE Pond Filters are named by the water volume of the pond they can cope with, based on no fish being in the pond.  So, for example, the FiltoClear 30000 Pressurised Filter can cope with a pond of up to 30,000 Litres with no fish, 15,000 Litres with small hardy fish or 7,500 Litres with Koi Carp.

Which filter is right for my pond?

As mentioned above, the most crucial factors are – how much water do I have and, what (if any) fish will I be keeping?  There are other factors to also consider, such as sunlight exposure and water depth (i.e. if you have a very shallow pond in full sunlight, the filter should be upgraded to help combat algae growth due to warmer water temperatures).  We have supplied a guide list of suitable filters below, based on the water volume without fish and assuming an ideal pond depth of 1 metre. 

To calculate the pond volume, simply measure the maximum length, width and depth in metres and multiply these together, then multiply by 1000 to determine the volume in litres.  For example:  L2.0 metres x W1.5 metres x D1.0 metres x 1000 = 3000 Litres.  We’ve stated the complete sets include pump and UV clarifier where possible, but many of these filters are available on their own, if you already have a pond pump and/or Ultraviolet Clarifier. 

A golden rule to remember;  you cannot ‘over-filter’ a pond but you can certainly ‘under-filter’ it!  Having a filtration system which is more than capable of dealing with the pond and its inhabitants is far better long term than a system which is just on the cusp of its limits.

OASE Pond Filter selection choices (based on pond water volume without fish):

Small Pond up to 3,000 Litres.

Filtral 3000 (compact all-in-one submersible filter with built-in pump, UV clarifier and filter media)

BioPress 4000 Set (cost effective pressurised filter with integral UV Clarifier and separate submersible pump)

FiltoClear 3000 Set (superb pressurised filter from OASE with integral UV and energy efficient pump)

BioSmart 7000 Set (Easy-clean Gravity flow through filter for pond-side mounting.  Complete with pump and UVC)

Small Ponds up to 6,000 Litres.

Filtral 6000

BioPress 6000 Set

Filtoclear 6000 Set

BioSmart 7000 Set

FiltoMatic 7000 Set (Self-cleaning pond filter with integrated UC Clarifier and Aquamax Eco Pump)

Small Ponds up to 9,000 Litres

Filtral 9000

BioPress 10000 Set

FiltoClear 12000 Set

BioSmart 14000 Set

FiltoMatic 14000 Set

Medium Ponds up to 12,000 Litres

2 x Filtral 6000 (multiple Filtrals can be used in ponds and water features for effective filtration)

FiltoClear 12000 Set

BioSmart 14000 Set

FiltoMatic 14000 Set

Medium Ponds up to 16,000 Litres

2 x Filtral 9000

FiltoClear 16000 Set

BioSmart 18000 Set

FiltoMatic 25000 Set

Medium Ponds up to 20,000 Litres

3 x Filtral 9000

FiltoClear 20000 Set

BioSmart 24000 Set

FiltoMatic 25000 Set

Medium Ponds up to 30,000 Litres

4 x Filtral 9000

FiltoClear 30000 Set

BioSmart 30000 Set

BioTec ScreenMatic 40000 Set (High-tech OASE filter system with self-cleaning mechanism, Bitron UV and Pump)

Medium Ponds up to 36,000 Litres

2 x FiltoClear 20000 Set

BioSmart 36000 Set

BioTec ScreenMatic 40000 Set

Large Ponds up to 60,000 Litres

2 x FiltoClear 30000 Set

2 x BioSmart 30000 Set

BioTec ScreenMatic 60000 Set

BioTec Premium 80000 (Filter only – Automatic filter drum for ultra-effective filtering in Koi Ponds)

ProfiClear Premium Compact (Filter only – new Automated Drum and Moving Bed Hel-X Biomedia)

ProfiClear Premium Filter Set 1 (Cutting-edge filter system with multiple filter modules and large drum filter technology)

Large Ponds up to 100,000 Litres

BioTec ScreenMatic Eco 120000 Set

Proficlear Premium Filter Set 2

Large Ponds up to 140,000 Litres

BioTec ScreenMatic Eco 140000 Set

Ponds/Small Lakes up to 200,000 Litres

Proficlear Premium Filter Set 3