How To Keep A Fish Tank Warm Without A Heater? 9 Tips For New Aquarists

Fish cannot create internal heat by themselves, so they require some assistance to maintain optimal body temperatures, especially in wintertime.

If your heater is broken, the power is cut, or you can’t afford to buy a specialized aquarium heater, these things can become a big issue.

On the other hand, temperature plays a vital role in determining the health condition of aquatic creatures because it regulates ammonia levels and oxygen.

How to keep a fish tank warm without a heater? Luckily, you can apply many methods to save your fish when there isn’t any heating system.

Let’s dive into this article to learn more!

What Are The Best Ways To Warm Your Fish Tank Up Without Using A Heater?

What should you do if your fish tank or heater is broken or the power is off? Don’t worry if this situation happens.

Below are the most practical ways to warm your aquarium without using a heater. Let’s take a closer look and pick out the most suited one!

Purchase Cold-Water Fish.

Coldwater fish are tough creatures that thrive in colder water. These animals can also withstand rapid temperature changes in the environment.

Fluctuations will happen if you build a tank but don’t use a heater. Choosing fish that can resist this typical situation will only help you succeed in the future.

Most coldwater fish require water temperatures of 60 to 74 degrees Fahrenheit.

Coldwater fish

Make Your Tank Smaller.

There are various advantages to choosing a smaller tank when it comes to heating.

The aquarium has a smaller amount of water, so it is easy to warm up. Hence, you may keep it in a relatively warm portion of your room.

A big aquarium helps keep a consistent temperature. However, it will waste more heat and require more work to heat up than one that is smaller.

As a result, you can consider a 20-gallon aquarium.

A smaller tank will not require a heater if your home is constantly warm. It can absorb warmth from the surrounding environment and remain in that heat.

Increase Your Home’s Temperature.

If you increase your home’s temperature where you put your fish tank, you won’t need a heater in that aquarium.

If there’s a specialized place exclusively for your fish, it may be costly. However, it is not a big problem if the space is already warm, like your living room.

If you put several aquariums in the same space, it may be more cost-effective to heat the entire room rather than treating each aquarium separately.

Most cold-water species will be ok if kept at a room temperature between 75 and 78 degrees Fahrenheit.

Use Warm Water If You Change The Tank Water.

Frequently changing the water can assist you in bringing the water temperature of your tank to the desired level without the help of a heater.

It would be best if you slowly increased the water temperature. Some fish types may suffer some problems if the temperature is raised faster than 1° every hour.

If you opt for this way, it’s better to remember to store more water than the required volume for the water-changing process.

For instance, you can combine room temperature water with a bit of hot water, but you should never pour boiling water straight into your aquarium.

Insulate Your Tank’s Glass Walls.

Have you set your tank’s water temperature to the desired level for the aquatic creatures you intend to raise?

If it’s the case, you can consider insulating all-glass walls.

Using polystyrene to cover the aquarium’s side panels and back isn’t the most aesthetic solution. Besides, an insulation sheet or foil is a viable option.

This strategy will keep the heat in, but you’ll have to conduct warm-water adjustments regularly.

It is the main disadvantage of keeping a tank without a heater.

Place The Aquarium In A Warmer Part Of The House Or Near A Heater.

Any house has cooler and warmer zones, so you may reap the benefits of the hotter places when you don’t want to use the heater.

Putting your fish tank in the warmest location of your house or near a heater is an excellent idea to help it earn some degrees without further effort.

What to consider while finding a desirable place to place your aquarium? Follow some tips below:

  • Move your tank to a higher floor because the top levels are often warmer.
  • Avoid drafty spots as they tend to be cold even when using a centralized heating system.
  • Choose a location in your house where the aquarium will receive natural sunshine each day for at least roughly 6 hours.
  • Have several algae-control products available if you pick the warmth-by-sunshine approach, as algae development can increase when a lot of sunshine flows in.

Warm The Water In The Tank Gradually.

Warm water adjustments work similarly, but it’s a little more complicated.

You may progressively warm the water in the aquarium by floating in a boiling water-sealed container.

To get an 80°F temperature in your aquarium, the water temperature of the floating bottle must be 120 degrees Fahrenheit.

Although this way is not the most efficient solution, it is the most practical option if you need a heater all the time in your fish aquarium.

It does, however, allow for some significant temperature changes. As a result, it’s not good to try it with sensitive fish species.

Warm water gradually

Invest In A Heating Pad.

A heating pad is a heating gadget that you may use to warm your tank temporarily.

All you need to do is to put your tank on top of the heating pad, connect it to the power, and switch it on. The gadget will uniformly heat the tank’s bottom.

Nevertheless, this equipment is frequently unregulated, causing the water temperature in the aquarium to rise over the allowed range.

The heat may shatter your aquarium. Alternatively, the tank may harm this heating pad.

Install A Heater For An Emergency

You can make an emergency fish aquarium warmer with a few common home items. All you need is candle wax or candles, a glass jar, and a bain-marie wick.

First, melt the candle wax or some candles. Then pour this wax into a big glass jar and keep the wick in the center to make a giant candle.

Let the jar cool down. After that, float it onto the aquarium. Light your big candle. Ensure nothing flammable gets near to the flame of a candle.

This method will work well if you apply it while insulating glass walls to maintain the generated heat.

Add-Ons That Will Help You Keep Your Fish Tank Warm Without Using A Heater

Apart from the solutions above to have a heater-free fish tank, you can also consider the following add-ons. Here are some examples:

Cover Your Fish Tank With A Hood Or Lid.

If you want to keep your aquarium warmer without the need for a heater, you can use a hood or lid to cover it.

This way, you may restrict the amount of water that comes into touch with a cooler breeze.

Most aquariums may be supplied with detachable tops, allowing you to track to the inside for maintenance.

A lid may reduce the number of oxygen levels in the tank, but you can use an air stone or an air pump to enhance oxygenation.

Cover your tank

Use Brighter Lighting.

Placing your aquarium under direct light from the sun or using artificial lighting with brighter lights might yield the same warming effect.

This way, you can easily control the amount of light to heat your aquarium.

In this situation, algae growth may still be a problem, but you may take steps to reduce it.

If you don’t have a heater, it’s better to turn on the light for 8 to 10 hours. Also, stronger and lighter lights will benefit the plants in the tank.

Make Layers Of Insulation.

This warm-up approach may be an eyesore for some aquarists. Nevertheless, the best approach to keep warmth in is to use insulating material on your system.

It is a simple and affordable addition that may have a significant effect.

If your house is freezing in winter or the average temperature fluctuates significantly during the day, this add-on will be more beneficial.

Make Use Of A Heating Mat.

Heating mats are specifically designed to keep terrariums warm. However, you can use them to heat a small tank.

To minimize hot zones and glass shattering, you’ll need to place a polymer film between the heating pad and the base of the bowl.

Glass is a poor heat conductor, and this addition is among the least effective. So, you can regard this way as an experiment.

Make Use Of A Non-Energy-Efficient Filter.

One of the most helpful ways to save your heater-free fish aquarium is to use a non-energy-efficient filter.

A less efficient filter system operates warmly since they consume so much excess energy. The filter’s engine can quickly warm up the water in the tank.

If you combine this method with a thermal barrier add-on, you might have a warm tank.

Use Blankets For Emergency Situations.

A blanket, especially a thick one, is the most effective insulating covering in an urgent situation.

In the event of a power loss, a blanket draped across the glass panels of the aquarium can assist keep the temperature stable and allow for a gradual cool-down.

Aquatic creatures that don’t adapt well to colder water might die from sudden temperature decreases.

Maintain Frequent Water Temperature Monitoring Using A Thermometer.

A thermometer can help you keep track of the water temperature in the fish tank and determine how effective your warming techniques are.

While you’re first setting up the aquarium, stay updated on the temperature in the aquarium to see its stable ranges.

You will experience a better time determining which types of fish will thrive in an unheated aquarium.

You should also utilize your freshwater test kit to evaluate if the temperature significantly impacts the general condition of your tank’s water.

Why Do You Need To Warm Up Your Heater-free Fish Tank?

Many experienced fish keepers wonder why they must keep your tank warm if there is no heater.

If you are in the same case, the following reasons should explain your question:

  • Power outages might occur in a short or more extended time than expected.
  • Heater replacement problems are unavoidable. When it comes to tropical fish, leaving the aquarium cold while setting up a heater repair might be dangerous.
  • Avoiding rapid water temperature dips becomes a need in generally warm places during odd spells of cooler weather.
  • The water will be much more extreme in the cold months. So, water in a heater-free tank may fluctuate.

Reasons for warming a fish tank

In An Emergency, How To Keep Your Fish Tank Warm Without Using A Heater?

If you are a beginner aquarist, you will be confused and worried if your heater system gets some problems.

How do you deal with these emergent cases? Don’t get yourself stressed! Below are some valuable tips for warming up a heater-free tank to consider:

  • Examine whether the fail-safe mechanisms are in place if you’ve already set up sump shut offs and backflow tubing.
  • It’s better to cover the tank’s top and glass panels. This way, you can keep the heat within a heated aquarium from escaping.
  • Always insulate the filter system. You may wrap it with blankets, cardboard, or thick towels.
  • Allow for some breathing space. It means that you should not entirely shut off the oxygen levels in the aquarium.
  • Do not over-inspect the fish when you remove the temporary insulating layers, some heat escapes.
  • Monitor the temperature of the water with a sticker thermometer.

While it isn’t the most precise thermometer, it can alert you when the temperature within the aquarium dips dangerously low.

  • Start warming up the aquarium without using a heater. If the urgent scenario persists and the water temperature falls dangerously low, use the ways above to heat things rapidly.

Fish Species That Are Adaptable To Changes In Water Temperature

Only cold water fish tolerates a heater-free arrangement for an extended period.

These types of fish can thrive in a wide variety of water temperatures and can survive significant temperature fluctuations.

The following are examples of tough species that can survive in water temperatures ranging from 60 to 74 degrees Fahrenheit.

Endler’s Livebearer

This cold-water fish is an excellent addition to any aquarium. They are not only bright and attractive but also simple to maintain.

These fish are highly resilient, adapting to various environmental and habitat conditions.

They have a range of temperature between 64°F and 84°F that they consider suitable.

Endler’s livebearer

Bloodfin Tetra

Bloodfin Tetras are one of the most favorite species in the aquarist community.

Like other varieties of tetras, these creatures are tiny and may be housed in a small aquarium.

When establishing their environment, you don’t need to worry much. These fish can survive in cold temperatures, a wide range of layouts, and pH levels.

They can survive and tolerate the water temperature from 64 to 82 °F.

Odessa Barb

These fish thrive in colder environments and get along with many other species.

Odessa Barbs will be content as long as you offer them a varied feed and a stable environment.

They can live in water ranging from 70 to 79 ℉, allowing them to be kept in aquariums without using a heater.

Odessa barb

White Cloud Mountain Minnow

The White Cloud Mountain Minnow is a fantastic freshwater fish species that can survive in frigid climates.

Many people mistake these creatures for Neon Tetras because of their similar appearance.

They’re relatively inexpensive, simple to maintain, and suitable for various species.

You may also raise them in various environments without problems, from 64°F to 72°F.

Sunset Variatus Platy

The Sunset Platy is a versatile fish that thrives in various environments. They require low maintenance and thrive in somewhat colder water (72°F to 82°F).

These are among the most vivid freshwater species. If you’re searching for a colorful cold-water creature, you can’t go wrong with them.

Sunset variatus platy

Panda Corydoras

These fish are among the most popular aquarium fish. Panta Corys may live in various habitats throughout the world.

They’re attractive fish with a distinctive color pattern. As a result, it’s fascinating to observe them swimming.

They’re calm, which means you’ll have many tank mates. They can suffer temperature ranges from 68°F to 77°F.

If you want to learn more about this species, you can watch this video:

https://www.youtube.com/watch?v=QryoFnSIYLA

Zebra Danio

The freshwater aquarists always look for this species. That’s due to its attractiveness as well as its simplicity of maintenance.

They are among the easiest fish to care for a beginner. They can live well in cold water at temperatures from 64°F to 74°F.

You can raise them in a small, frigid aquarium without worries about their nutrition or relationships with other species.

Zebra danio

In A Nutshell

After reading this article, have you known how to keep a fish tank warm without a heater? We hope your answer will be yes!

You can apply many ways to warm up a heater-free aquarium, like purchasing coldwater fish species, making the tank smaller, using heating pads, and more.

If you know other methods, feel free to comment below. Thanks for taking the time to follow this post!