Aquarium Heaters

Adjustable aquarium heaters from 25w to 300w to keep tropical fish at the right temperature.

Buying guide

Sizing a heater is straightforward: around one watt per litre suits a tank in a heated room, and nearer two watts where it sits somewhere cooler such as a hallway or conservatory. Position it close to the filter outflow and the warmed water is carried right around the tank rather than pooling in one corner. Pairing a heater with a separate thermometer gives you an easy at-a-glance check that the temperature is holding steady, which is why you will find both here.

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    2 products

    Aquarium Fish Tank Heater – 25w to 300w
    5 models
    Aquarium Fish Tank Heater – 25w to 300w
    from £13.49
    50w Fish Tank Aquarium Heater Sold out
    50w Fish Tank Aquarium Heater
    £7.99

    Not sure which heater?

    What wattage do I need?

    Around 1w per litre of water, sized up for a cold room

    Nano or small tank?

    Compact heaters suit tanks under about 30L

    Worried about knocks?

    Choose a model with a guard or shatterproof body

    Want it steady?

    An adjustable thermostat holds temperature without fiddling

    Fish Tank Heating at AllPetSolutions

    Maintaining the right water temperature for your aquarium is very important to ensure your plants and fish stay in tip-top condition. We stock a vast range of aquarium heaters, so you can keep the temperature where it should be for healthy aquarium inhabitants, and a selection of aquarium thermometers, perfect for monitoring the exact temperature of your tank.

    Setting up a new tank? Pair your heater with our aquarium filters, fish tank lighting and aquarium gravel and sand to complete the setup.

    Browse our fantastic range of aquarium heaters online:

    How do Heaters for Aquariums work?

    An aquarium tank needs a heater to be kept warm, particularly for exotic species of tropical and marine fish, which need warmer water to stay healthy.

    Our best aquarium heater range yet features the most advanced products, with easy installation, thermostat automatic heating control, and energy-efficiency to make warming your fish tank economical and easy. The general rule is to apply 1w of heat to 1 litre of water in the aquarium.

    Heaters for aquariums convert electricity into heat, and the water quickly absorbs this warmth. To ensure that all parts of your tank are equally comfortable, and to avoid dangerous hot or cold spots, it is essential to have good circulation or install an air pump or wavemaker.

    Are Heaters for Aquarium Tanks expensive?

    Not at all, the AllPetSolutions range features the best aquarium heater brands, including our own market-leading range.

    This includes every accessory you need for your heaters for aquarium tools, from digital thermometers to heater guard protectors and a range of high-performance heater options.

    Our newest models include our 100W Aquarium Fish Tank Heater, which is entirely submersible and has a smart nickel helical heating coil for outstanding performance and durable design.

    Available in a full choice of heat ranges from 300W, down to 25W versions, our bestselling heaters are cost-effective both to buy and to run and come complete with a one-year warranty for peace of mind.

    Can I keep track of the temperature in my aquarium?

    Many aquariums heaters come complete with thermostatic controls. However, it is always nice to have visibility of that temperature and make sure that the warmth is just right for your fishy pets.

    AllPetSolutions offer a range of thermometers, from our simple Digital Strip through to Glass Floating Precise Aquarium Thermometers.

    For guidance about the best aquarium heater products, visit our range online, or get in touch with the AllPetSolutions team for expert guidance.