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Thermakoi Pond Heaters


Regular price $929.95

Protect your Koi from the cold winters and treat your koi to the best Koi Pond Heaters! 

Koi Fish immune systems are at their best in steady water temperatures around 75 degrees. During the cold winter, Koi stop eating and live off their fat reserves, lowering their immune system. As the water begins to warm up, bacteria become active, and Koi can be in trouble. Keep your Koi strong all winter by heating your pond which allows you to continue to feed your koi all-year long.

Easy To Install: 

In the past, it hasn't been easy to heat koi ponds.  It meant getting plumbers out to run gas lines or propane lines. Now, with the ThermaKoi line of heaters, life just got easy for you and more comfortable for your koi. The smallest unit the 1.5 kW unit plugs directly into a regular 115-volt outlet and the larger sizes (6 kW, 11 kW, and 18 kW are hardwired (230 volt) into the built-in junction box that comes with the units.


  • Made of 316 stainless steel and utilizing highly accurate electronic thermostats, these units keep the water temp constant all year round.
  • Installs easily and quickly -- plumb in line with included 2" slip unions
  • Overload protected and built to last


Heaters come by default with analog controls. For an additional $140, heaters can come with a digital display.

Model Wattage Max Pond Size Power Cord Type
ThermaKoi 1.5 1.5 kW 500 gallons 115V plug with GFCI
ThermaKoi 6 6 kW 6,000 gallons 230V hardwired with junction box
ThermaKoi 11 11 kW 11,000 gallons 230V hardwired with junction box
ThermaKoi 18 18 kW 18,000 gallons 230V hardwired with junction box