Do Guppy Need Heater? 5 Best Heater For Guppies

Guppies need ideal water temperatures of 71 to 82 degrees Fahrenheit for their survival. Icy weather conditions can give rise to various ailments and infections that can even take a guppy’s life. Guppies need a heater in their water tank to maintain the ideal water parameters.

This also reduces the chances of temperature fluctuations and keeps the dangers at bay. A 5-gallon or a 10-gallon tank would usually require a 75 watts heater.

Also, you must position the heater near the water filter, which would circulate the hot water and keep the temperature evenly distributed throughout the tank.

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Do Guppy Need Heater?

do guppy need heater
does the guppy need a heater?

Yes, it would help if you put your guppies in a tank that has a heater. This is not just to keep the water temperature within the ideal range of 71 to 82 degrees Fahrenheit but also to avoid temperature fluctuations.

Too much temperature fluctuation is associated with many diseases and disorders that can even cause death in guppies.

Hence, to maintain a steady temperature throughout the tank, one needs to invest in a good-quality heater. Frigid temperatures make your guppies lethargic and can severely weaken their immune system, and this makes them suffer from serious ailments (fin rot or dropsy).

Do All Guppy Need Heater?

Yes, all guppies need a heater in their tank. Guppies are tropical freshwater fish that can not survive in extreme temperature conditions, and they can be happy and healthy when the water temperature stays between 71 to 82 degrees.

A heater keeps the temperature constant and avoids unwanted temperature fluctuations in the tank.

When Guppies Need Heater?

Guppies usually need a heater when the temperature fluctuates and does not stay in the optimum range of 71 to 82 degrees Fahrenheit.

It is important to note that they find it difficult to survive in extremely cold or hot environments.

These extreme weather conditions can lead to various health issues in guppies and make them passive, and they may also cause suffocation and a decrease in oxygen levels.

The best thing about a heater is that it keeps the water temperature steady and does not allow fluctuations of any kind, reducing the chances of ailments in guppies.

Factors To Consider Before Buying Heater For Guppies

Guppies need a heater to keep them safe and healthy. It reduces the likelihood of fluctuations in water temperatures and keeps the temperature constant inside the tank.

This is important for their survival as they cannot endure extreme temperatures. But before you go and buy a heater, there are certain factors that you must consider.

First of all, you need to determine the appropriate size of your heater based on the size of your tank. Five watts per gallon of water is the basic rule you must follow while buying a heater.

( For example, if a 5-gallon tank needs a heater of 25 watts, a 10-gallon tank would require you to buy a 50-watt heater).

This would ensure that the water temperature inside the tank remains ideal and stable.

Next, the size of the tank will determine the type of heater that needs to be bought. If you have a large-sized tank, you need to buy a filter heater. As it is almost invisible, guppies are less likely to damage the heater.

If there are live plants inside the tank and you need a heater that heats the water uniformly, you should go for a substrate heater. As the name suggests, it heats the substrate in the fish tank and makes the water warm.

Uniform heat distribution in the water is the most significant advantage of using a substrate heater. As it is embedded inside the substrate, guppies can not see it and hence can not cause any damage to it.

If you have a freshwater aquarium and need to buy a heater at an affordable price, there is nothing like a hang-on heater. They usually hang on the top edge of the tank and have a glass tube consisting of the heating material, which gets dipped into the tank water.

5 Best Heater For Guppies

5 best heater for guppies
5 best heater for guppies

What should you do if your tank is small and you need a heater for your guppies? Do you need to purchase a large tank? Or do you have to buy a small affordable heater? Let us clear all the doubts with this post.

You will be happy to know that there are heaters in the market specifically made for small tanks and would not consume a lot of space inside the tank.

They would also maintain the ideal water parameters of your tank without you having to invest in a larger tank. If you want to heat the tank water conveniently, below are a few tips that would help you pick the best heater for a five or a 10-gallon tank.

First of all, understand that guppies need warmer temperatures to stay healthy. This means a heater should not be avoided. It helps lower the chances of temperature fluctuations in the tank, leading to various diseases and even death in some cases.

Buying a 50-watt heater would be sufficient for a 10-gallon tank. It would help if you also looked at the temperature adjustability. You may have to purchase a temperature controller for a heater that has a preset temperature.

Here are the five best heaters that you can choose to buy for your guppies:

1. FreeSea Submersible Heater

FreeSea submersible heaters are specially designed for small-sized fish tanks. They do not consume too much space in the tank and are ideal for small aquariums.

They also have an LED temperature display available in various power sizes. These heaters need to be submerged in water and should not stay dry.

It would help if you never forgot to unplug this heater before changing the water or cleaning the aquarium to avoid overheating issues. You can set the ideal temperature range (71 to 82 degrees Fahrenheit).

It works efficiently in maintaining a steady temperature as it has an automatic steady temperature feature. This means the heater automatically turns off when the required temperature is attained and can turn on again if the temperature begins to go below the optimum range.

The LED display of this heater helps you monitor its functions more conveniently. You will get this heater with a 1-year warranty.


  • Compact size with a round shape designed for people who do not prefer cigar-shaped heaters.
  • It Comes with a 1-year warranty.
  • This HEATER Has an LED display for better functionality.
  • It acts as a built-in thermostat for better temperature adjustability.


  • It is not recommended for small fish
  • Too much overheating when running dry.

2. Aqueon and Global Mini Heater

The Global Mini Heater is another good option with temperature adjustability features that can be used in your small tank.

It is a preset heater and has a preset temperature of 77 degrees Fahrenheit, and this means you do not need to make any manual temperature adjustment to this heater.

It comes in two sizes. One is for smaller tanks (up to 5 gallons), and the other is larger ( from 6 to 10 gallons). This heater is constructed with PPC plastic and is relatively easy to be installed in the tank by using the suction cups that come in the kit. It also contains a red-colored LED indicator that will inform you when the heater is working.

This heater is designed explicitly for small-sized water tanks, which need a heater that consumes less space and keeps the water temperatures warm and steady.


  • Does not consume too much space.
  • Can be easily installed with suction cups.
  • Comes in two different variants depending upon the size of your fish tank.
  • The temperature variation does not exceed 1 degree.


• Temperature controller needs to be bought for additional safety.

• Manual temperature adjustment is not possible.

3. Tetra HT Submersible Heater

The Tetra HT Submersible heaters are available for various tank sizes (2 to 55 gallons).

It comes with a built-in thermostat that helps to keep the temperature steady at 78 degrees Fahrenheit.

It also contains heat, indicating LED lights. This helps you monitor the tank water temperatures accurately. ( Red light indicates that the heater is on, and a green light indicates that the desired temperature has been attained).

It is a fully submersible heater, and it can be installed either horizontally or vertically. As it is small and compact, you can easily hide it under the live plants and decorations of the tank. It has a beautiful turn-off system that turns the heater off in electrical shorts.

However, you need to use a temperature controller to turn it off when needed. Small tanks dissipate heat much faster than large ones due to minor water volume. Hence, using a hood with your aquarium is essential to retain the heat and enhance the heater’s efficiency.


  • Can be easily installed in any position.
  • Comes with LED light indicator for better monitoring.
  • Has a built-in thermostat.


  • Preset heater with no manual adjustment options.
  • May produce a lot of heat.

4. Fluval Submersible Heater

This submersible heater comes with a temperature dial at the upper side of the heater, which means you can adjust its temperature.

It comes with brackets and suction cups for easy installation. The heating element is made with high-impact, durable glass.


• Compact and affordable.

• Temperature dial for manual adjustments.


• A thermometer is needed.

5. Aqueon Submersible Heater

Aqueon Flat is another submersible heater suitable for small-sized tanks.

It is completely submersible and can be installed horizontally or vertically. It also saves a lot of space in the tank and is very affordable.

Thye are shatterproof heater and is best for desktop-style aquarium tanks, and it is ideal for a 10-gallon tank.

Like most submersible heaters, it should not be allowed to run dry. This heater does not have any LED light indicator.


  • Very affordable.
  • Keeps the water temperatures stable.
  • Space-saving design.


• Does not come with an LED indicator.

• Temperature can not be adjusted.

Guppy Heater Ideal Temperature

Heaters should never be avoided for your guppies. You need to invest in a heater to make sure the water temperature inside the tank remains ideal and steady.

The ideal water temperature in the water tank ranges from 78 to 82 degrees Fahrenheit, and a heater helps maintain this ideal range.


Do Guppy Need Heater In Australia?

Yes, guppies need a heater in Australia. They are tropical freshwater fish, and it is almost impossible for them to survive in extreme temperatures, leading to various diseases and infections.

A heater would ensure uniform distribution of heat throughout the fish tank and maintain steady temperatures in the water.

Do Guppy Need Heater In Uk?

No, it is not compulsory to have a heater for your guppy in the UK. The United Kingdom is a temperate climate zone which means the temperatures never go to the extremes here.

This is the best condition for the survival of your guppies as they are tropical freshwater fish and survive best in temperate conditions.

Do Guppy Fry Need Heater?

Though it is not mandatory to use a heater for the guppy fry, they may need it, and this is because guppy fry does not grow very fast without the heater.

A heater also ensures that the tank water temperature remains ideal and within the range of 78 to 82 degrees Fahrenheit.


Buying a heater is always a wise investment for your guppies. They need ideal water temperatures for their survival.

Any temperature fluctuation can be dangerous for guppies as they survive best in moderate temperatures.

Extreme temperatures can also give birth to many serious ailments such as fin rot and can also lead to the death of the guppies in some cases.

Therefore, you must buy a good-quality heater to keep the water temperatures steady and within the range of 78 to 82 degrees.

The guppy fry may not need a heater, but it can certainly help them grow at a rapid rate.

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