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Oase HeatUp


Oase HeatUp aquarium heaters are a range of high precision fully submersible heaters suitable for any type of aquarium. They can be used as sand alone heaters or run inline inside one of Oase’s BioPlus internal, or Oase’s FiltoSmart or BioMaster external filters.


Clear selection


Oase HeatUp heaters are automatic submersible heaters for use in fresh and saltwater aquariums in the home. They also fit neatly into Oase’s range of Oase’s BioPlus internal filters, the FiltoSmart or BioMaster external filters.

Easy to set the temperature

The desired temperature is easily set. Simply dial the regulation pin on the top of the heater to change the set temperature. You can see where the temperature is set on the front of the heater.

HeatUp size guide for Oase Filters

When used inside of Oase filters, these heaters work much more efficiently because water flows across them constantly and then pushes the heat around the aquarium. Below is a list showing which sized heaters are compatible with the Oase filters that we sell:

  • 50W – BioPlus 50
  • 100W – BioPlus 100
  • 200W – BioPlus 200, BioMaster 350
  • 300W – FiltoSmart 300, BioMaster 600
  • 400W – BioMaster 850

HeatUp Size guide

The size of HeatUp that you need depends on how you are using the heater and on your ambient room temperature, a size guide is given below:

For standalone heating (when not using inside of the Oase filter range).

  • 25W heats 15 – 25 litres
  • 50W heats 25 – 50 litres
  • 100W heats 50 – 100 litres
  • 150W heats 75 – 150 litres
  • 200W heats 100 – 200 litres
  • 300W heats 200 – 300 litres
  • 400W heats 300 – 400 litres

If your room temperature is very cool, allow more wattage for heating the tank properly.

If your aquarium is larger than 400 litres, you can use two heaters. Use the above guide. For example, a 500 litre aquarium in a cool room would need 1 x 300W plus 1 x 400W heater.

How to work out your aquarium’s volume

If you are not sure how large your aquarium is, it is easy to work out. Measure the length, width and height of the tank in cms. Times those three measurements together. Then divide the result by 1000. This will tell you how many litres the tank can hold. Allow some displacement for the aquarium décor. Remember that if you have an external filter or sump tank, these can also increase the aquarium volume. You can work out the extra volume in the same way.

(L X W X D)/1000=litres

How to measure temperature

Even though we’ve found these heaters to be extremely reliable, we still recommend checking the aquarium temperature regularly. At Cornwall Aquatics, we take a quick look at the thermometer every time we feed the fish. Here are some thermometers that we sell:

Thermometer – JBL Digital Strip

Thermometer – JBL Slim Glass

Also, if you keep a marine aquarium, the Hanna Salinity Tester is a great way to check temperature too.

Additional information


25W, 50W, 100W, 150W, 200W, 300W, 400W


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