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Ultra Violet Clarifiers and related electrical accessories

At Koi Water Garden, we are able to offer competitive prices on not only high quality koi, but also on koi related goods such as UV clarifiers, water pumps and other electrical accessories.


last updated 10th July 2019

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Ultra Violet Lamp systems


Yamitsu UV systems


Yamitsu UVs are one of the best selling UV systems and have been in production since 1990. They are manufactured from UV stabilised materials and are rugged and reliable, They are now also one of the only UV systems available which are fully CE compliant for electrical safety, featuring for example, safety clamps holding the UV tube in place to prevent accidental removal. They are fully electronically controlled for reliability and long life - and importantly to ensure low running costs. Did you know that the average UV system using 'conventional' electro mechanical control gear consumes over four times as much electricity as an electronic model? So a conventional 30 watt UV can actually consume as much as 160 watts of power! They are easy to install with all models featuring glued hose tail connections for flexible pipe work, and 1.5" inlet/outlet ports ready to glue to solid pipe work connections too. They also come complete with mounting clamps. All models are easily serviced and control gear can be replaced if required. Still the most cost effective UV systems available.  When calculating the size of UV required, start on the basis that 10watts is required for every 1000 gallons.



Model Wattage Price
Yamitsu 15 15 £76.50
Yamitsu 30 30 £112.50
Yamitsu 55 55 £136.50
Yamitsu 110 110 £249.00
Yamitsu 220 220 £475.00
Philips/Osram long life UV bulb 15 £10.50
Philips/Osram long life UV bulb 30 £16.50
Philips/Osram long life UV bulb 55 £21.50
Quartz sleeve 15 £18.00
Quartz sleeve 30/55 £34.50

Yamitsu Electronic UV


Please note that shipping charges for UV bulbs and Quartz sleeves are £9.95 per package. These charges may not show in the shopping cart and will be applied regardless of order value or content when bulbs or quartz sleeves are included in any order. 




EVO electronic UVs


The new Evolution Aqua evoUV deliver a more efficient and more economical performance than before thanks to their new design. The new range includes completely redesigned 30 Watt and 55 Watt models, a new 15 Watt and 25 Watt model perfect for use on the smaller garden pond, along with a 75 Watt version. The top end 75 Watt model is designed for ponds up to 75,000 litres. The highly efficient ballast and high output 75 Watt UV bulb provides a more economical option than a traditional 110 Watt UV due to the greater UV contact time offered by the 1.2 metre bulb – ultimately saving you money! The design of these new UVs optimises flow rates and improves energy efficiency, with the sole focus to deliver optimum performance at all times to clear green water in ponds which is caused by single celled green algae. evoUVs will work alongside many different filtration systems and are incredibly easy to install with flexible hose or hard pipe and can be easily fitted within existing pipework runs. All evoUV models come with high output UV bulbs powered by energy efficient ballasts, all housed within a fully watertight, robust housing.



Model Wattage Max Pond size (gallons) Price
Evo 15 15 3,000 £82.99
Evo 25 25 4,400 £87.99
Evo 30 30 6,600 £122.99
Evo 55 55 12,000 £137.99
Evo 75 75 16,500 £159.99
Evo 110 110 33,000 £245.95
Philips/Osram long life UV bulb 15 £10.50
Philips/Osram long life UV bulb 25 £14.50
Philips/Osram long life UV bulb 30 £16.50
Philips/Osram long life UV bulb 55 £21.50
Philips long life UV bulb 75 £39.50
Quartz sleeve 15 and 25 watt £28.50
Quartz sleeve 30 and 55 watt £34.50
Quartz sleeve 75 watt £39.50

Please note that shipping charges for UV bulbs and Quartz sleeves are £9.95 per package. These charges may not show in the shopping cart and will be applied regardless of order value when bulbs or quartz sleeves are included.



Oase Vitronic UV


At last Oase have come up with a range of small, neat and compact UVs but packing the same power as much larger units. With the ability to mount these units vertically as well as horizontally, and very competetively priced, and of course with Oases renouned build quality, this range is a real winner.


These all new Oase UV sterilisers feature :-


  •  Compact design, small footprint, only 53cm - 66cm long
  •  Reduction of harmful bacteria and pathogen level
  •  Electronic ballasts for low energy consumption
  •  Visual function check of the UVC bulb
  •  Quick release for easy bulb change and cleaning of the quartz glass
  •  High quality workmanship with light weight impact resistant plastic housing
  •  Thermal safety protection
  •  The ability to be mounted vertically as well as horizontally
  •  Easy installation thanks to an extensive range of connection accessories
  • 100 %, VDE-certified safety; does not cause eye injuries



Model Wattage Max Pond size (gallons) Price
Vitronic 18 18 4,000 £99.99
Vitronic 24 24 5,500 £109.99
Vitronic 36 36 8,800 £149.99
Vitronic 55 55 13,000 £169.99
18 watt UV bulb 18 £26.50
24 watt UV bulb 24 £29.50
36 watt UV bulb 36 £32.50
55 watt UV bulb 55 £38.50

Please note that shipping charges for UV bulbs and Quartz sleeves are £9.95 per package. These charges may not show in the shopping cart and will be applied regardless of order value when bulbs or quartz sleeves are included.



Bitron Gravity UV

These all new UVs from Oase are , as far as we know, the first units to be made available for pump or gravity installations. They can be mounted for gravity flow inside or outside of a filter chamber, can be mounted vertically or horizontally, and most importantly offer virtually no flow loss potential owing to the 110mm inlet and outlets and very large body. This means they are ideal for very high capacity pumps such as the Oase Aquamax Expert range, the Eco Titanium, the Blue Eco range and the Flow Friend


These all new UV sterilisers feature :-


  • Extremely effective elimination of suspended algae and reduction in pathogenic bacteria levels (at 12.5 m³/h) - similar to an immersion UVC
  • 100 %, VDE-certified safety; does not cause eye injuries
  • Particularly energy efficient thanks to electronic ballast
  • Unusually effective sterilisation, thanks to long water contact time in the Bitron
  • Flow-optimised reactor design ensures direct and virtually loss-free UV radiation
  • High-quality V4A stainless steel housing for stability and good reflection rates
  • Extremely easy installation with stainless steel connection elements
  • Flexible connection before or after the filter system on pump fed filter systems.
  • In the event of pond enlargements or increase in koi stock, extension with additional Bitron Gravity UVC devices is possible at any time
  • Visual function check
  • Horizontal or vertical setup possible
  • Incl. 2 x DN 110 quick release couplings, easy to install
  • Also suitable for pump fed operations
  • Suitable for ponds to 70 m³



Model Wattage Max Pond size (gallons) Price
Bitron gravity 55 55 15,000 £459.00
Spare bulb 55 - £59.99



Below - Bitron gravity UV Below - Showing vertical installation Below - Installed inside filter module

Please note that shipping charges for UV bulbs and Quartz sleeves are £9.95 per package. These charges may not show in the shopping cart and will be applied regardless of order value when bulbs or quartz sleeves are included.




Delta Bio - UV germicidal sterilisers

These all new UV sterilisers use a completely different wavelength of UV light, i.e. 30,000 µ/sec/cm2 which effectively kills a wide range of organisms in pond water, especially Aeromonas and Pseudomonas bacteria and many types of virus. The units also feature special bulbs which have an effective life of over 1 year or 9000 hours and use very little electricity making them extraordinarily cost effective.


Exclusive features of this range include a 316 Stainless Steel housing that allows for 360° rotation of the inlet and outlet unions for ease of installation, simple design of the lamp chamber that makes bulb changing a simple job that can be accomplished by even the least mechanically minded person in 2-3 minutes. Another key exclusive features not commonly found in similar units is the inclusion of unions at each end of the Stainless Steel housing, which allows for 360° rotation of both inlet and outlet ends for universal piping options as well as the total disassembly of  the Stainless Steel housing to facilitate cleaning of the quartz tube, should it be necessary. Units can be installed indoors or outdoors, in a horizontal or vertical position, with mounting simplified by utilizing the Stainless Steel mounting legs supplied.


The high output (HO) low pressure lamp is capable of 30,000 µ/sec/cm2 output when design flow rates are maintained. This is the same requirement as for drinking water, so you can be assured of the highest quality water standard. No other system in this price range has been so extensively safety and performance certified. Units are supplied with 2" demountable connectors for ease of maintenance.



Model Wattage Max Pond size (gallons) Price
Bio Uv 35 35 1,500 £475.00
Bio Uv 55 55 4,400 £595.00
Bio UV 90 90 5,500 £695.00
Bio UV 110 110 6,600 £759.00
Spare UV bulb 35 £75.95
Spare UV bulb 55 £109.00
Spare UV bulb 90 £136.00
Spare UV bulb 110 £159.50
Delta Bio UV

Please note that shipping charges for UV bulbs and Quartz sleeves are £8.00 per package. These charges may not show in the shopping cart and will be applied regardless of order value when bulbs or quartz sleeves are included.



Powersafe Switch boxes and cable joiners

Ensure your electrics are professionally completed and safe. Water and electricity don't mix!


Cable connectors and switch boxes are IP rated for peace of mind. The multi way connector allows you to connect 3 devices to one supply.


Powersafe switch boxes are rated at 1 x 1kw connection and 2 , 3 or 4 at 500watts. All individually fused with power on indicator light and individually coloured inputs and on/off switches.


The Powersafe range (see right) are IP 56 rated, have power on, standby and power off illumination for each circuit, and are very rugged and simple to wire owing to the comprehensive installation and wiring instructions supplied. They also come complete with a range of pre-printed labels for each circuit and spare fuses.


The Aquasafe cable connector is an ideal underwater waterproof connector for all pond electrics:-


  • Polycarbonate body
  • Tested to IP68, at 2 bar
  • Joins cables from 5mm - 9mm
  • Cost effective
  • Quick connect and release with a snap lock collar
  • More reliable than screw-thread connectors
  • Active latch mechanism for quicker wiring 


Product Price
Aquasafe Waterproof Cable connector £13.95
Multiway Cable connector £17.50
3 Way Powersafe switch box £39.50
4 Way Powersafe switch box £55.50
5 Way Powersafe switch box £72.50

Above: Multiway cable joiner, with cover off

Powersafe switch box

Above: Powersafe four way switch box.

Above: Aquasafe underwater cable connector

Matsuko intelligent Switch boxes


The new Matsuko Switch Box range gives you five lines for five different devices with a stylish, but simple on and off button giving you full control over your electrical pond products. These Switch Boxes are great for controlling multiple pond, garden and aquarium appliances, each outlet will take appliances of up to 1500 watts per line and a maximum load of 3000 watts.

The unit is fully versatile outdoors being extremely durable and waterproof, complies with at least IP56 (to IP66 dependent upon installation method).


    New Features include
  • New quick release electrical terminal blocks
  • New position for the terminal blocks for easier connections
  • New improved electronics


The Programmable Switch box is equipped with a 5-way programmable Timer.  Each device connected can be individually programmed to turn on or off 5 times per day.


The top of the range Switch Box Timer + Pump guard also has the added bonus of PumpGuard and a power consumption monitor.


What is PumpGuard?   PumpGuard is patent pending, smart technology that helps to avoid possible disasters occurring when your pump blocks or overloads.


Line 1 on every Matsuko Switch Box Timer + PG is set to automatically learn how the new pump behaves when it is first connected and turned on through the timer. The PumpGuard will run the pump at different power levels for a twenty-minute period until it understands its normal operation, once this has been learnt the PumpGuard goes into monitoring mode.


Product Price
Matsuko 5 way switch box £79.95
Matsuko 5 way Programmable switch box £109.95
Matsuko 5 way Programmable switch box with Pump Guard £158.95



Matsuko Switch Box Timer + PG also features a power consumption monitor.


In this situation PumpGuard sounds a stop alarm (the signal for a pump failure alarm is a fast beeping sound plus a red LED on line one) and the display shows “pump fail“.

The digital display on the Pumpguard screen gives two electrical consumption readings. The Switch Box Timer + PG gives a constant reading on line 1.


The second reading on the screen shows a total consumption of all the lines being used by all the devices on the Switch Box through lines 1 – 5. To get a reading for an individual line simply switch off every line you do not want to monitor. The consumption monitor gives an indicative reading with an accuracy of +/-5%.


PumpGuard will monitor the pump all day everyday looking out for signs of overloading or cutting out. A pump that constantly keeps restarting can easily burn itself out.


PumpGuard detects this situation and will run the pump on a lower intensity programme to see if this will correct the problem. If a solution cannot be found, PumpGuard will disconnect the power and save your pump from damaging itself further. 

Matsuko Switch box

Above: Matsuko 5 way switch box

Matsuko Switch box

Above: Matsuko 5 way Programmable switch box.

Matsuko Switch box

Above: Matsuko 5 way Programmable switch box with Pump guard





Automatic Water Top up Kits 

These super auto-top up kits can be purchased complete or as individual elements to build your own system. A neat float valve, easily located in a filter tank or similar, acts as a simple switch to activate a motorised valve which turns on and off the water supply as required. The valve is operated via a 25v transformer.




Product Price
Float Switch £22.95
Motorised Valve £32.95
Transformer £24.95
 Automatic water top up system

Pro-Line Automatic Water Top up Kit 

This auto-top up kit is purchased as a complete kit - ready to go and features a float switch already linked to a weatherproofed motorised solenoid valve. The float switch can be mounted using a 1.5" bracket on to any convenient point, such as the pond wall or inside the filter chamber. Supplied complete with click hose fittings




Product Price
Pro-Line Auto Top up kit £199.95
 Pro-Line automatic water top up system

Oase Pumpguard Automatic Water Top up Kit 

The Oase auto top up system is a top quality product. Features an electronic controller wired to a double probed sensor linked to the controller and motorised solenoid valve. The level sensor is designed to be mounted on the pond wall or inside a suitable filter chamber.




Product Price
Oase Pumpguard Auto Top up kit £339.00




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