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How to Heat Up Fish tank Water Quickly

how to heat up fish tank water quickly
It’s the time of the year when the air gets cooler and the weather chillier. At this time, you have to be thinking about heating up your fish tank water. This guide on how to heat up fish tank water quickly includes equipment and manual solutions.


Heat Up Fish Tank Water Using a Water Heater

The surest way to heat up fish tank water is using a water heater for aquariums. Invest in good quality water heaters, and it should be a long-lasting solution.

It generates heat as long as it is turned on. You would not need to check the temperature all the time.

These heaters are attached to the tank, submerged in water, with a suction. Their power source is a cord that runs out. Most heaters already come with a built-in temperature setter. Just set the temperature you want the water to be, and the heater will do the rest of the work.

After a while, check the thermostat. When the desired temperature is reached, turn the heater off.

Heat Up Fish Tank Water Naturally

If you do not yet have the means to get a water heater, you can try these methods to heat up tank water naturally.

Turn Up the Room Temperature

Turning up the room temperature can also affect the water in the fish tank. This method will only take a few hours, but it has a prolonged effect.

Set the room temperature to 21-22°C so your fish tank water can gradually heat up. It may prove dangerous to the fish if there is a sudden temperature rise.

Frequently check the temperature of the water. Is it hot enough? Is it too hot? Be careful not to overheat it. Make adjustments to the room temperature if need be.

Move the Fish Tank Near a Heat Source

One heat source you can find in a house, especially during winter, is the fireplace. It would do your fish good if you could move the fish tank close. But do not place the fish tank too close.

You can also try moving your fish tank near to a vent. This method can quickly regulate the water temperature to heat up. So note that it should not be done for long hours as the water may overheat.

Another heat source is light. If your aquarium has lights, turn them on. You can also direct light from the outside to your aquarium. Make sure to use soft lights and do not expose your fish to light all the time.

Heat Up Fish Tank Water Naturally with D.I.Y Methods

heat up fish tank water naturally

What if you do not have electricity? What if there is no power source? What is the quickest and safe way to heat up the fish tank water?

Use Plastic Bottles

You might be wondering how to heat up fish tank water quickly using plastic bottles? Easy, with hot water.

Prepare plastic bottles that fit in the aquarium. Pour hot water in them, then seal the caps on. Place the plastic bottles in the aquarium. Let them float until you notice the change in the temperature.

If there is no heat left in the bottles and the water is still a little too cold, just change the lukewarm water in the bottles to hot water. Repeat this process until the tank water reaches its ideal temperature.

This method does take time and effort, but it can be your best solution when there is no electricity.

Wrap with Warm Blankets

A similar method with the plastic bottles is using a warm blanket; heat up a blanket big enough to wrap around the aquarium. Place it near the base of the tank and use two or three blankets if you want to see results faster.

This method, however, only lasts for a few minutes. However, you can always change the blankets, although it is more work than you might like.

Keep in mind that this solution is for when you have no other choice. It is when there is no electricity-generated heat available for you to use.

Surround with Heating Pads

Heating pads could provide instant heat to your fish tank. To keep the heating pads attached to the tank, you can use blankets. Warm blankets are best to hold the heating pads and help keep the tank water warm.

This method heats up the water quickly and provides a long-lasting effect. Heating pads are also helpful tools in maintaining the water temperature warm.

How Long Does it Take for Water to Heat Up?

Did you just notice that your fish tank water is too cold that you came to ask how long it takes for water to heat up?

Water heaters are the quickest way to heat up your fish tank water. Depending on the amount of water, the kind of water heater, and the initial temperature, it could take 30 – 80 minutes for the water to heat up.

I encourage you to invest in a good quality water heater to make it easier for yourself to heat fish tank water.


With all the methods listed above, make sure that you check the water temperature regularly. It is essential for the fish to live in well-heated water. They need it to survive the winter months. It is better if you could already start planning how to heat up fish tank water quickly before winter comes.

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