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Dormer Cottage, Spurgrove Lane, Little Frieth,

Nr. Henley on Thames, Bucks, RG9 6NU

Phone/Fax: 01494 882600

Koi Pond Heating Equipment

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 Remora Air Source Heat Pumps, electric heaters, heat exchangers, and other accessories.

 

last updated 11th January 2022

 

 

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Heating your Pond - is it necessary? - What's the best method?

 

Well frankly - NO - you don't have to heat a koi pond. Koi are poikilothermic, which means their body temperature is governed by the surrounding water temperature. They are hardy 'cold water' fish which will withstand and proliferate in a wide range of water temperatures. Koi have been known to survive temperatures of 1 Deg C (33 Deg F) up to 32 Deg C (90 Deg F) without ill effect. It is not the extremes of temperatures which seem to bother Koi, but rather the duration of any temperature extremes and rapid temperature fluctuations which can cause problems for the Koi keeper.

 

In the UK, the problems are generally not associated with extremely cold water temperatures during winter, but rather the length of our rather dreary, 'cold' and miserable winters and low water temperatures which cause problems. A Koi's immune system functions properly at temperatures over around 12.5 Deg C ( 55 Deg F). Under this and the immune system ceases to function effectively and at lower temperatures, a Koi's ability to fight diseases can be severely reduced. Unfortunately, many pathogenic bacteria and a range of parasites can survive and even proliferate at temperatures down to around 5 Deg C, meaning that your Koi are at their most vulnerable at temperatures of between 6 Deg C and 12.5 Deg C.

 

As water temperatures in the UK can be in this range for up to 5 months of the year, you will appreciate why it is that most of the disease problems with which we as Koi keepers are faced (generally in Springtime) may be precipitated by this length of relatively cold water temperatures.

 

In addition, smaller ponds of say, 2000 gallons or less will be more prone to the affects of unstable water chemistry as the pond volume is comparatively small and even in ponds with a larger volume but of a shallow nature can exhibit the same problems. Any water parameters which change too quickly will stress the Koi. One of these water parameters is obviously water temperature, and ideally, this should not fluctuate by more than 0.5 deg C per day.

 

Over winter, and indeed in Spring, we may get very cold and frosty nights, but followed by sunny days, which can result in temperature fluctuations of up to 2 deg C or even more in small, unheated, shallow and uncovered ponds. The degree of temperature change obviously varies across the UK but one of the most important benefits of heating a Koi pond is the ability to achieve a stable water temperature at all times.

The objective of any heating installation is therefore not to heat the pond to high temperatures for reasons of, for example, high growth, or just to keep our koi active. It should be targeted at controlling the water temperature to avoid the temperature 'trap' or the fluctuations described above.

 

In our own installations, we heat our stock (and private) ponds until Christmas time, by leaving the pond thermostats set to 16 Deg C ( 61 Deg F). This extends the Koi's Summer and keeps them feeding and growing well. From around the turn of the new year we then progressively turn down the temperature by 0.5 Deg per day until the water temperature returns to ambient levels (whereby the water temperature falls to match the surrounding average air temperature). We then give all our Koi a shortened winter for about 1/2 of January and all of February and then switch the heating on again at the beginning of March. During these cold months we allow the water temperatures to drop as low as we can , normally down to 4 or 5 Deg C. This does absolutely no harm to healthy Koi for this short period but helps to 'cleanse' the pond environment and reduce the numbers of any remaining parasites or bacteria.

 This means that we are effectively giving the Koi a 10 month Summer and a maximum two month Winter. We are also only using our heating systems for around 4 - 5 months of the year, and not heating at all for the two coldest months, January or February, and since we are not trying to raise our pond temperatures to ridiculously high levels, we are also reducing extra fuel bills as much as possible.

 It is an established and accepted fact that Koi live longer if given a 'natural' winter, and we do NOT subscribe to the view that Koi ponds must be heated all the year round to ensure their well being. Indeed we would go further, in that ponds that are heated all the year round must be maintained much more carefully to avoid problems as the Koi never get a period of 'rest' or inactivity and a Summer maintenance regime is absolutely vital to ensure that no problems are encountered. Weekly water changes and filter maintenance must be adhered to whilst water temperatures are elevated simply because whilst you are providing a warm comfortable environment for your Koi, you are also providing the same conditions for parasites and bacteria which can and often do multiply very quickly in ponds kept 'warm' during winter, whilst the not so vigilant Koi keeper is snuggled up in front of a log fire with ample supplies of mince pies and Brandy, completely forgetting about daily or even weekly pond maintenance tasks!

 

 If you do decide to heat your pond you will have a number of options, including heating using gas, oil, electricity and now electricity in the form of air source heat pumps. Whilst Gas installations are more expensive to install, they are comparatively cheap to run.   Oil is now becoming very expensive, and the capital outlay for an oil installation is generally also more expensive than a gas installation. Direct electric heating systems are easy and relatively cheap to install, but are the most expensive to run - Now however with the introduction of air source heat pumps, you have the ability to increase the efficiency of your heating system installation by up to 400% as air source heat pumps can deliver up to 14 times the energy consumed and are now by far the cheapest method of heating your pond ( see below). However - the choice is yours!

 

To give you an idea of costs, Gas systems can cost as little as 70p per thousand gallons per day to run, whilst oil is currently around £1.00 per thousand gallons per day, and direct electric heating costs start from around £1.30p per thousand gallons per Day.

 DC inverter air source heat pumps can cost as little as 50p per thousand gallons per day.

 

Insulating a heated pond is vital for keeping costs under control and even a simple cover made from a heat retentive material such as bubble wrap or (ideally) polycarbonate will reduce costs substantially. As an example we have halved the costs of heating our 25,000 gallons of stock ponds by covering all the heated ponds with triple wall polycarbonate sheet. The costs of the insulation will pay for itself in the first season.

 

 

 

Air source Heat Pumps.

 

 

What is a heat pump?:- A device that converts electrical energy to kinetic to thermal energy through the use of compressed refrigerant. It works like a refrigerator in reverse. It draws heat from the air, and transfers that heat to the pond water. A heat pump does not create heat like a resistance heater, it extracts heat from one location and transfers it to where it is needed.

Heat pumps operate on the principle of a closed circuit similar to that used in the household refrigerator. One side is cold the other hot. For instance a refrigerator removes heat from its inside as well as from the food, and transfers it via the condenser to the outside air, which is warmed.

 

Heat Pumps utilise the sun’s free heat by collecting and absorbing energy from the outside air. This energy is then transferred to the koi pond water. Your existing koi pond pump circulates the water through the heater which warms the pond. The unit contains a fan that draws in outside air and directs it over the surface of the EVAPORATOR (energy collector). The liquid refrigerant within the EVAPORATOR coil absorbs the heat from the outside air and the refrigerant becomes a gas. The warm gas passes through the compressor where it is compressed to form a very hot gas, which then passes through the CONDENSOR (water heat exchanger). It is here that the heat exchange occurs as the hot gas gives up the heat to the cooler koi pond water circulating through the coil. The pond water becomes warmer and the hot gas is cooling down as it flows through the CONDENSOR coil, returns to its liquid form and, after passing through the expansion valve, the whole process begins again.

 

Depending upon the design of the installation and ambient temperatures, it is possible to get in excess of 14 times more heat per kw of power consumed using the latest heat inverter heat pump technology. So for every 1kw of power consumed, up to 14kw of heat can be produced to heat the water.

 

Inverter heat pumps are the latest type of heat pump to be made available and are even more efficient - up to 20% more efficient than a standard A/C heat pump. This is because DC (direct current) technology is around 96% efficient compared to A/C technology (alternating mains current) which is only around 46% efficient. In addition, with DC technology the compressor within the heat pump can change speed as the heating demand varies, so that when an inverter unit is first switched on, it will run at full power. As the water temperature approaches the set point, it will slow down and run at a lower power rating and within the set temperature range the heat pump will be running at a low power level, therefore consuming less electricity. With an A/C model, the unit is either on or off, and when on and running the unit will run at full power. So inverters are able to vary the load to suit the heating requirement and therefore will cost even less to run than even their A/C counterparts.

 

Inverter models are more expensive to buy, so have not been commonly used in Koi pond heating, however now inverters are more competitively priced, and indeed some are cheaper to buy than many of the older technology A/C models. All of our heat pumps are now offered with a three year parts and labour warranty which is backed up by nationwide distribution and so now has never been a better time to invest in these super efficient units.

 

All types of Heat pumps are at least 3 times more efficient than other heating methods including gas, oil, and direct electric. Savings in terms of running costs can be as much as 70% less than for direct electric heating, and up to 40% less than oil or gas.

If you do decide to heat your pond, air source heat pumps are undoubtedly by far the most cost effective method of doing so, being economical to purchase and install when compared to gas or oil installations as well as being cheaper to run, and are way way cheaper to run than direct electric systems.

 

Remora Heat Pumps.

 

 

The latest heat pump range are from Remora - an ultra modern heat pump which are super efficient, and are very competitively priced. The range is offered with a three year parts and labour warranty and seven year warranty on heat exchanger and compressor (parts only after third year) Wi-Fi connectivity built-in* allowing remote control of the operation and settings, high efficiency performance with advanced stepless DC inverter systems on inverter models that automatically control the running speed of the compressor and the fan. Super quite in operation 30db at 10m range. Heating and cooling modes, works efficiently down to - 15 deg c. Black ABS corrosion resistant cabinet. Features EEV throttling technology which adjusts the gas flow and increases COP by up to 20%, Spiral Titanium heat exchanger is 40% more efficient than standard titanium heat exchangers. Uses R32 gas for environmentally friendly operation. Winter cover included as standard

 

Remora® heat pumps are ideally suited for heating Koi ponds:
  • Wide range of set points from 5°C to 40°C
  • 13A RCD plug on 6kW, 8kW and 10kw models allows you to plug units directly into outside sockets without need for additional electrical connections
  • 10m extension cable on Wi-Fi module for improved connectivity to home Wi-Fi networks
  • Suitable for all year round heating / cooling
  • Remote input for external third party thermostatic management, for example RS PRO On/Off Temperature Controller
  •  

     

    In summary:-

    • Premium Inverter heat pumps with built-in* Wi-Fi connectivity
    • 6kW 8kw & 10kW plug & play models, come complete with RCD and 13A plug fitted
    • Ideal for Koi ponds, wide range of set points from 5°C - 40°C
    • COP of up to 8, up to 8kW of heat for every kW power used
    • Extremely quiet running, maximum 30 dB(A) at 10m
    • Heats and cools, reverse defrost cycle, R32 refrigerant
    • 3 year parts & labour, 7 years on compressor & heat exchanger (parts only)
    • Requires professional electrical connection on largest models

 

 

Model Remora 6 Remora 8 Remora 10 Remora 12 Remora 15 Remora 20 Remora 23
Heating Capacity (max kw) 6 8.8 10.5 12 15.8 20 23.3
Max Input power (kw) 0.85 1.21 1.38 1.67 2.03 2.71 3.74
Max Current (amps) 3.9 5.36 6.26 7.75 9.42 12.13 17.01
COP at 15 deg C 5.4 5.4 5.7 5.5 6.13 6.04 5.16
COP at 25 deg C 7.2 7.2 7.58 7.2 7.85 7.42 6.23
Max pond size (gallons) 3000 4000 5000 6000 7000 10000 12000
Dimensions L x W x H mm 826*379*552 933*401*657 933*401*657 935*401*657 1125*470*707 1125*470*707 1125*470*707
Weight (kg) 44 54 57 72 75 78 94
Noise Level DBA <30 <30 <30 <30 <30 <30 <30
Price 975.95 1217.95 1335.60 1399.00 1695.00 2542.00 3175.00
Order

 

 

Remora Inverter Heat Pumps.

 

 

The latest inverter heat pumps are from Remora - an ultra modern heat pump range which are super efficient, and are very competitively priced. The range is offered with a three year parts and labour warranty and seven year warranty on heat exchanger and compressor (parts only after third year) Wi-Fi connectivity built-in* allowing remote control of the operation and settings, high efficiency performance with advanced stepless DC inverter system that automatically controls the running speed of the compressor and the fan. Super quite in operation 30db at 10m range. Heating and cooling modes, works efficiently down to - 15 deg c. Black ABS corrosion resistant cabinet. Features EEV throttling technology which adjusts the gas flow and increases COP by up to 20%, Spiral Titanium heat exchanger is 40% more efficient than standard titanium heat exchangers. Uses R32 gas for environmentally friendly operation. Winter cover included as standard

 

Remora® inverter heat pumps are ideally suited for heating Koi ponds:
  • Wide range of set points from 5°C to 40°C
  • 13A RCD plug on 9kW and 12kW models allows you to plug units directly into outside sockets without need for additional electrical connections
  • 10m extension cable on Wi-Fi module for improved connectivity to home Wi-Fi networks
  • Inverter model is suitable for all year round heating / cooling
  • Remote input for external third party thermostatic management, for example RS PRO On/Off Temperature Controller
  •  

     

    In summary:-

    • Premium Inverter heat pumps with built-in* Wi-Fi connectivity
    • 9kW & 12kW plug & play models, come complete with RCD and 13A plug fitted
    • Ideal for Koi ponds, wide range of set points from 5°C - 40°C
    • Average COP of 10, up to 10kW of heat for every kW power used
    • Extremely quiet running, maximum 30 dB(A) at 10m
    • Heats and cools, reverse defrost cycle, R32 refrigerant
    • 3 year parts & labour, 7 years on compressor & heat exchanger (parts only)
    • Requires professional electrical connection (15kW, 19kW and 27kW mode

 

 

 

 

Model Remora 9 Remora 12 Remora 15 Remora 19 Remora 27
Heating Capacity (max kw) 9 12 15 19 27
Max Input power (kw) 1.35 1.86 2.24 2.87 5.22
Max Current (amps) 6.8 9.1 11.5 14 25.5
COP at 15 deg C 8.2 8.2 8.5 8.1 8.0
COP at 25 deg C 17 18 18 18 15
Recommended max pond size (gallons) 5000 9000 12000 14000 18000
Dimensions L x W x H mm 826*379*552 826*379*552 933*401*657 1125*470*707 1125*470*707
Weight (kg) 35 37 47 61 66
Noise Level DBA <30 <30 <30 <30 <30
Price 1588.95 2008.95 2118.95 2995.00 4446.95
Order

 

 

Digital Thermostats.

A necessity if you heat your pond, gives very accurate control down to + or - 0.1 Deg C resolution. Fully adjustable, weather proof (splash proof) and ideal for Gas or Oil installations. Complete with thermostat probe cable (5 metres) and power connections. LED display. Not suitable for the control of direct electric heaters.

 

 

 

Type Price
Pro-line digital £159.50
 Digital thermostat

Digital Thermostats - relay controlled.

A necessity if you heat your pond using direct electric heating, gives very accurate control down to + or - 0.1 Deg C resolution. Fully programmable , weather proof (splash proof) and can also be used for Gas or Oil installations. Complete with thermostat probe cable (5 metres) and power connections. LED display. Suitable for use with mains powered heaters up to 3kw. .

 

 

 

Type Price
Pro-line digital £225.50
 
Digital thermostat

Stainless Steel Heat Exchangers

These are made from high grade stainless steel and incorporate thermostat probe pockets and 1.5" or 2" male threaded pipe fittings.

 

Capacity/Max flow Price
60,000 btu, 900 gph £250.50
100,000 btu, 1440 gph £265.50
130,000 btu, 1860 gph £295.95
170,000 btu, 2460 gph £319.50
230,000 btu, 3300 gph £385.50
460,000 btu, 6600 gph


 
£895.00


 stainless steel heat exchanger

IR Infra Red Pocket Thermometer

This super little pocket thermometer reads remotely by using Infra Red technology - just point at the water and press the button to get an accurate and instant reading of water temperature. No probe, no wires, no contact with the water. Powered by 2 x AAA batteries, the unit utilises an LCD display which reads from -50 and + 350 deg C, with a resolution of 0.1 deg C - the unit comes complete with batteries. Reads in Celsius or Fahrenheit.

 

Model Price
IR Pocket £26.95
 

Pro-line Titanium pond heater systems.

These all new heater units have Titanium heating elements for good resistance to chemicals, especially salt in the pond water, and therefore have a long life. Accurate to + or - 0.1 deg C the special thermostats have an internal relay that allows them to be used on a wide range of applications including gas and oil boilers as well as electric heaters up to 3kw. They also now feature thermal cutouts and reset buttons. To calculate the correct heater size you will need a minimum of 1kw per 1000 gallons. All the units in this range can be connected to a normal domestic 13amp mains supply.

 These new Pro-line heaters also offer ultimate flexibility in that the heaters and thermostats can be used independently. Should either unit fail, they can therefore be replaced individually and systems can be upgraded from 1kw to 2kw to 3kw using the same thermostat.

 

 

 

Model Price
1kw, 5 amp £395.00
2kw, 9 amp £419.00
3kw, 13amp £445.00
1kw, 5 amp, Element only £158.00
2kw, 9 amp, Element only £179.00
3kw, 13 amp, Element only £196.00
 Pro-line heater

 Pro-line heater

Cloverleaf pond heater systems.

The New Cloverleaf Pond Heaters are fully EU, TUV and UL approved they are available in two size 1kw and 2 kw. The Cloverleaf Heaters are very easy to install into new or existing pond setups and come complete with both rigid or flexible pipe connections. Choose from connection via 19mm, 25mm, 32mm or 38mm flexible pond hose using the 2 hosetails supplied or alternatively the units will accept 40mm rigid solvent weld or 1.5” rigid pressure pipe. These simple easy to use pond heaters have a minimum flow rate of 4000lph and have a safety low flow shut off switch for peace of mind

 

1kw and 2kw power consumption 4000lph minimum flow rate with pressure switch Thermostatically controlled IP55 rated 1.5m cut end cable fitted Flexi hosetails plus Solvent weld inlet and outlets length 230cm, width 18.5cm, hight 18.5cm  

 

Model Price
1kw, 5 amp £149.95
2kw, 9amp £169.95
 Pro-line heater

Xclear Proficlear pond heater systems.

 

The Xclear Profi Pond heaters are the latest heaters to be introduced to the Aquatic Market place and for those Koi keepers that are having to work on a budget they are available at a very realistic price. The Profi Pond Heaters have a fully calibrated Thermostat for easy control of pond water temperature. They also act as an ideal emergency back up for any gas or oil heated pond. Easy to install into existing pipe work. Supplied complete with couplings on the inlet and outlets allowing you to remove from pipe runs. Profi Pond heaters are simple to install into any system. The Profi Pond Heater incorporates a stainless steel inner lining and Stainless Steel heating element.

 

 

Model Price
1kw, 5 amp £212.00
2kw, 9amp £232.00
3kw, 13amp £239.00
  • 1kw, 2kw and 3kw power consumption
  • 4000lph minimum flow rate with pressure switch
  • Thermostatically controlled IP55 rated
  • 1.5m cut end cable fitted
  • Flexi hosetails plus Solvent weld inlet and outlets
  • Stainless Steel flow tube and heating element
  • 220-240v single phase
  • Analgue Thermostat

 

 Pro-line heater

Elecro Nano Cygnet in-line heaters.

 

The Elecro Nano Cygnet Heater range is a plug and play heater system incorporating a Titanium technology for a very long life and durable operation. They are are of a very high quality and very robustly put together. They are offered in a range of power outputs from 1 to 4kw and can act as an ideal emergency back up for any gas or oil heated pond, or can be used as the main form of heating for any suitably sized pond. Easy to install into existing pipe work. Supplied complete with couplings on the inlet and outlets allowing you to remove from pipe runs for servicing, Elecro Nano Cygnet heaters are simple to install into any system.

 

 

Model Price
1kw, 5 amp £330.00
2kw, 9amp £360.00
3kw, 13amp £390.00
4kw, 17amp £415.00

 

  • Various power options ranging from 1-kW to 4-kW
  • Easy installation, fully equipped and pre-wired
  • Robust, durable construction
  • Ultra-reliable flow switch allows safe operation
  • Supplied with temperature thermostat and overheating sensor
  • Compact, durable design
  • Analogue control with 1.2°C differential
  • Titanium flow tube and titanium heating element
  • Can be floor or vertically wall mounted
  • Vortex, long life, stay clean heating element technology
  • 100% efficiency throughout the product life
  • 220-240v single phase
  • 1 to 17 cu m / hour flow rate
  • Features safety thermal cutout with manual reset
 Elecro Nano Cygnet Heater

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