How to Cool Down an Aquarium Without a Chiller

Heating an aquarium is actually a simple matter, but cooling it down in the midst of a sweltering summer can be quite a difficult task. Buying a chiller is usually a last resort due to the fact that they are very costly. So people try to come up with other methods to cool down their aquarium. That’s why we’ve chosen to provide this guide for you on ways to cool down your aquarium without using a chiller.

What is a Chiller

An aquarium chiller can best be described as being like a small refrigerator. This is then installed in-line with an external filtration system to cool down the water in the aquarium when it passes through it.

When you combine a chiller with a thermostat, the chiller can keep the aquarium water from rising above a pre-determined temperature. This is crucial when you have cold water fish.

You can use an aquarium heater to keep the water warm for any tropical fish you own, and a chiller will allow the aquarium to remain cool.

Most people who have aquariums, especially beginners at this hobby, do not need to have a chiller. Besides being costly, these are basically for more advanced aquarium systems.

Normally, chillers are created with larger aquariums in mind. This is partly due to the fact that most fish that need chillers are larger types of fish and they also require larger aquariums. Furthermore, cold water fish have a tendency to need more room, so that also makes a larger aquarium necessary.

Because chillers are so costly, they usually aren’t stocked in your area pet store, as they are not frequently required. Another reason for this is that most people who keep aquariums do not keep the types of fish that need a chiller.

Cooling Techniques

There are a variety of ways you can cool aquarium water. These are:

1. Use Fans

If you don’t want to purchase a chiller, but prefer to depend on cheaper ways of cooling, you can enlist the help of small fans to drop the temperature of your aquarium.

Use a small fan or a utility fan to send cool air out over the aquarium and thus help it remain fresh and serene. The fans, however, must be very quiet so that the fish won’t be upset by the noise.

Also, turn the room fans ON and place them so that your aquarium is getting the air from them. If this fails to do the job then install fans directly on the aquarium.

Place your fans in a position where they are right on the aquarium, and you can also install fans in the aquarium itself.

There are plenty of clip-on fan systems that you can buy. They are cheap and will serve the purpose just fine.

2. Air Conditioner

Instead of merely using fans, you might consider using the air conditioner. Since the purpose of an air conditioner is to cool the whole room, it should keep the aquarium cool too. Also, when the room is cooled due to the use of an air conditioner, the aquarium walls become cooled too and will then absorb that coolness inside of them and into the water. So this is the recommended way to keep your fish and aquarium equipment cool without using a chiller.

Other cooling methods serve to make the water cool, but the equipment such as lights and filters keep on operating and thus they make their own heat and warm the water up again. By using an air conditioner, you ensure that all of the equipment remains cool as well as the water itself. This way your needs are being met as well as those of your fish.

3. Ice Bag

Before you attempt to employ this manner to cool down your aquarium, you should be aware that you must do so very carefully. If the water is cooled too quickly, then your fish can become ill or even die. This is why this technique should only be used as an emergency measure to cool the water when there is no other method available to lower the water temperature.

Ice can turn the water freezing cold very swiftly. So you shouldn’t put ice cubes or an ice pack directly into the water. This will cause the water to become drastically cold within seconds, and your fish will not respond well to this.

Rather than doing that, put the ice cubes or ice pack into a sturdy plastic bag. Put this bag in the aquarium and allow it to slowly cool down the aquarium.

One more thing you can try is to close the equipment and lights that create so much heat. However, be certain that there is a steady flow of oxygen within the aquarium, and do not leave the fish in complete darkness.

A gradual change in temperature is the best way to go so as not to upset the delicate balance in your aquarium. So do not add more ice cubes or ice packs in the bag until the previous ones are melted. And always keep your eye on the temperature of the water. Once you’ve cooled it down, you might not have to keep repeating the process if the atmosphere of the room the tank is located in changes.

You don’t want to find yourself confronting the opposite problem of having made the water too cold for your fish. Just be careful and watch the temperature and everything should be fine.

4. Cold Water Bottle

You can take a cold water bottle and place it in your aquarium and allow it to float. However, the bottle should not be frozen. There should just be the cold water in it to cool the water. Don’t place an unclean bottle in the water of your aquarium or it will do more harm than good.

Only in a case where it is exceedingly hot outside and there is no other solution available to cool down the aquarium should you use a frozen water bottle to lower the temperature.

5. Open the Hood

During the summer you should absolutely not cover your aquarium with a hood to avoid any chance of your fish suffocating.

There must always be proper aeration entering the tank. Proper cooling within the tank is essential as well so that your fish can survive the summer happily.

While the use of fans or an air conditioner, will work well to cool down the water, it will not be effective if you have covered your aquarium with a hood.

6. Relocate Aquarium

Yet one more thing that you can do to help your fish is to move the aquarium to a better location which is cool and airy. Do not leave your aquarium in a hot, overloaded room.

When the water of your aquarium becomes hot it causes the fish to suffocate. They cannot endure this continuously, so it is a safe measure to move the aquarium and equipment to a better location.

One area you could put it would be where there are windows and the air is coming inside the room. This will be great for the fish, but be certain that there is no directly sunlight landing on the fish.

7. Water Circulation/Surface Agitation

Circulating water stays cool, that is why it is an excellent way to keep the temperature in your tank low. The circulating water dispels the heat outside, the carbon dioxide evaporates, and new oxygen is received into the tank.

In order to keep the water flowing properly, you need to use a pump. This is the natural way of keeping the water continually cool. It is also referred to as surface agitation.

8. Exhaust Fans

Turning on the exhaust fans is an effective method to cool down your aquarium if used along with other techniques.

You could try placing a cold water bottle in the tank and turning on the exhaust fans in your room. This will work very well in eliminating the heat from outside.

An exhaust fan is an excellent investment, for your home as well as for your aquarium. By controlling the room temperature and keeping it comfortable, you will also manage to keep your aquarium cool too.

9. Change Part of Cold Water

You can also drain half of the water from the aquarium and add new water which is a few degrees lower. Particularly if you own a large aquarium, this way of lowering the temperature in the tank is not going to be detrimental to the fish.

The more often you change the water, the lower the temperature will drop, but don’t overdo this because if the temperature is lower too much, then your fish can go into shock. Just use your common sense.

10. Install Drip System

With a drip system the cold water will continually drip inside the aquarium. It provides a non-stop flow of cold water for your fish to enjoy, and will do quite well in lowering the water temperature for your fish.

Just adjust the drip system whenever you need to by increasing the flow of water.

By using this method you should successfully be able to have the temperature remain cool and constant.

What Safeguards Should Be Used to Cool Down an Aquarium?

You need to take the following precautions when cooling the water in your aquarium.

  •  Do not make any abrupt temperature changes or radically change the temperature, but do so only by a few degrees in order to protect your fish. You do not want your fish to go into shock.
  •  Do not place your cold water fish in the same aquarium with any warm water fish you may have such as guppies and tetras.

Cold water fish need a temperature that is extra cool in comparison with tropical fish. Just as the tropical fish can become sick in water that is too cool, so can cold water fish become ill in water that is too warm. If you use the ice technique, be certain that you do not let the temperature rise and fall.

Keep an eye on the thermometer to check the temperature levels so that you can have the temperature remain constant. It is important to keep the temperature levels even and not allow them to drop suddenly and then shoot up again.

The ice technique is not meant to be a permanent solution to the problem of how to cool down your aquarium. Only use it temporarily because of the risk of fast and drastic temperature changes.

If you’re looking for a permanent solution to this issue, then use any of the other methods that have been mentioned above.

How Fish Respond to Changes in Water Temperature

As the temperature of the water increases, a fish’s metabolic rate and activity level also rise, which results in its requiring more oxygen. The capability of the water to hold onto dissolved oxygen decreases with a rising temperature, causing your fish to be in double trouble. It is critical that you have a working thermometer on your aquarium at all times and check it repeatedly the hotter the weather gets.

Indications Your Fish Are Stressed in Hot Weather

The first clue that your fish are experiencing stress due to hot weather is if you see them gasping for air at the surface of the water. If your fish are stressed this is not good for them, because their immune systems become compromised and they are apt to become ill.

If things should become more extreme, you will certainly be aware that there is a problem, and if you fail to or are unable to make the appropriate adjustments to the water in your aquarium, you may find yourself coping with the deaths of your fish.

The bottom line is that while anyone can obtain a chiller if they want one, in most cases this is a costly piece of equipment that can be done without. All you need to do is follow the advice given above and you will be able to expertly cool down your aquarium without having to resort to as extreme a measure as buying a chiller. Just always keep in mind the health and safety of your fish whatever approach you decide to take to keeping the water in your tank at the appropriate coolness. As long as you make the welfare of your pets a priority, then you should be able to make the right decision for your aquarium.