Can You Keep Your Fish Tank Outside

Can You Keep Your Fish Tank Outside?

It takes time, work, knowledge, and experience to create the best environment for aquatic life. The stability of the system depends on a lot of things, like where the aquarium is.

Today, we’ll talk about how indoor and outdoor tanks are different and what you need to know if you want an outdoor tank.

Most people have aquariums inside, but when it comes to bigger aquariums, many people prefer to have them outside.

But, as you will see, outdoor tanks have their own problems that require a lot of creativity and knowledge to solve.

Can You Keep A Fish Tank Outside?

The short answer is yes! You can put your aquariums outside, either on the balcony or in the backyard. This will give the fish plenty of time alone while keeping the aquarium out of your way. 

But putting a fish tank outside can be harder than putting it inside and has more negatives than positives. So, there are many things you should think about before going with this option, such as the surrounding environment, design lighting, temperature, maintenance time, fish species, etc.

5 Things To Consider When Keeping A Fish Tank Outside

When you keep a fish tank outside, there are a few things to think about, like where you put the tank, how hot or cold it is outside, what kind of fish you keep, how big the tank is, and what might eat the fish. Let’s look at each one in more depth:

Place Of Your Tank

It makes a huge difference where you put your tank. Even though there are a lot of things to talk about here, like how stable the aquarium is, how much wind it gets, or how bad the weather can be, we will focus on the most important thing: sunlight. To begin with, fish don’t need too much light.

After all, most fish in aquariums live in places with medium to low light. Most aquarists turn on brighter lights so they can see the fish better, not so the fish can see better.

If you put your aquarium in direct sunlight, the fish will get stressed and there will be a lot of algae.

Algae grow well when there is a lot of light and quickly take over their environment when the conditions are right. You can lessen the effects of the algae by putting live plants in the tank.

These things will take up room and eat the nutrients that algae would like to have. This will keep algae away, but it won’t work if you don’t control the light.

If there isn’t enough light or it doesn’t last long enough, algae will take over, flood the habitat, cover the plants, and make it hard for them to get light.

This could kill your plants because they won’t be able to do photosynthesis.

Fish may also start to die as they get caught in the dense masses of hair algae, which look like real webs in the water.

To keep this from happening, you should always keep your aquarium in a cool, safe place that is away from direct sunlight, strong winds, rain, and other weather.

This is not enough to keep algae from growing in your aquarium, but it’s a good start.

Temperature Changes

All fish in a tank need to be kept at a certain temperature to stay healthy and active over time. Most fish that live in warm water will do well in water that is between 72 and 82 degrees Fahrenheit.

Changes in temperature don’t have to be a problem because all fish can adjust to them.

It’s normal for the temperature of the water to change during the day.

The problem is sudden or repeated changes in temperature that could throw off the balance of the system.

Your fish might get a temperature shock, which would make them show signs of stress. These include being sleepy, swimming in a strange way, not wanting to eat, breathing quickly, and so on.

If the water in the tank is too cold, your fish will swim less to save energy. If the temperature doesn’t return to normal, they could have temperature shock, become too cold, and die.

Or, if the water gets too hot, your fish will start to suffocate because oxygen levels drop faster in hotter water. Temperature changes are more extreme in tanks that are outside than in tanks that are inside.

Keep the tank out of direct sunlight and use a heater to fix the problem. Even more so if you live in a place where the temperature changes a lot from day to night.

Also, you should always think about where you live before you set up an outdoor tank. If the temperature outside changes a lot from one season to the next, you might want to bring the tank back inside when it gets cooler.

For example, guppies are tropical fish that can’t live in temperatures lower than 70 F. They might be able to make it for a while, but eventually they will get sick.

The more likely it is that your guppies’ immune system will get sick, the colder the water is. All tropical fish are the same way.

Fish Species

There are a lot of fish that can live in tanks and ponds outside, and there are just as many fish that can’t. Carps like goldfish, koi, Hi-fin sharks, and other carps do well outside.

These fish are adaptable and tough enough to live in some of Mother Nature’s worst conditions.

Tropical fish like guppies, plecos, and just about any other kind should be kept inside. The temperature, as you may have guessed, is the most important thing here. Tropical fish need warmer water and stable temperatures.

You could keep them outside, but it’s not likely because you can’t really control the temperature of the water like you can in an indoor tank.

So, be careful when you choose your fish species to avoid a disaster.

Size Of The Tank

This is usually a matter of personal taste, but keep in mind that larger tanks are usually more stable. The temperature will change more quickly in smaller tanks, and they will need more cleaning and maintenance.

So, you should think about getting a tank that is at least 75 gallons for outside. This should be enough to keep the system stable and give your fish enough room to be happy and healthy.

When it comes to how it looks, the size of the tank is also important. Most people keep fish outside in big ponds, which makes them easier to clean and care for.

If you want an aquarium instead, find the best place to put it from the start.

This will keep you from having to move the aquarium if the environment doesn’t work out the way you want it to.


You might not have thought about this one, but it is a real danger. Aquariums and ponds that are outside are semi-open places because they are close to nature.

This makes it easier for many predators to find your fish and eat them. Pond fish are often hunted by birds, small reptiles, and even mammals when no one is looking.

Putting the fish in a tank outside might make them even more at risk. At least a pond is usually darker, so fish have somewhere to hide.

Even more so if you have a lot of live plants to hide behind.

A tank, on the other hand, is a flashier place with clear walls. The live plants you already have won’t do much to hide the shape of your fish. If anything, the live plants will make the fish stand out because they change the fish’s color and behavior.

So, always be on the lookout for possible predators that could hurt your fish. Once they smell your fish, they will stay in the area and come back as often as they need to keep attacking them.

By putting a lid on the tank, you can keep potential predators away. Make sure it has holes in it to make sure it gets enough oxygen and to stop dangerous CO2 from building up.

What Fish Can Live In Outdoor Fish Tanks?

Any fish can live in an outdoor tank with the proper preparation and awareness. Guppies and other tropical fish that require more controlled environmental conditions are included.

The temperature is your primary concern here. Your fish will thrive regardless of where the tank is located as long as temperatures remain stable.

Goldfish and koi, in my opinion, are the kings of outdoor aquariums. These are adaptable and hardy, but they require a lot of space and intense cleaning on a regular basis. They are well-known for producing massive amounts of waste, which can quickly overwhelm the environment.

They also require deeper waters and more swimming space than smaller species that are better suited to indoor environments.

If the aquarium conditions are stable, mollies, swordtails, gouramis, and other similar fish can easily adapt to an outdoor life. So it all depends on how involved you are and how well you optimize their environment.

Never Let Water Freeze In A Glass Tank

If you live in a place where the temperature changes a lot from day to night, you should buy a heater. Do this even if your fish are cold-water animals that are used to living in colder places.

When things are just right, the water in the tank can get very cold very quickly. This can cause your fish to get too cold and die quickly.

I think you should try things out first. Set up the aquarium, add the plants and decorations, and leave the tank outside for a few days to a week before adding the fish.

During this time, keep an eye on how the temperature changes and how it changes depending on the time of day.

This will show you how to set up the heater so that it works best and the temperature doesn’t change too much.

How To Maintain A Fish Tank Outside?

Even though it’s not a problem to keep a fish outside, there will be other problems that you won’t find inside.

If you’ve decided to put an aquarium outside, there are a few things you need to know about how to keep it in good shape.

Consistent Temperature

If the temperature goes up and down, it could kill your fish.

So, no matter what kind of fish you have, you need to make sure you can keep the water temperature in the right range.

To do this, you can use an aquarium thermometer to keep the temperature stable and the water level the same.

Oxygen And Filters

Oxygen is one of the most important things that an aquarium needs to be healthy.

The fish will suffocate if there isn’t enough oxygen, and too much oxygen can cause gas bubbles to form in its heart, which will kill it.

So, make sure your fish tank has enough oxygen and that it is kept at the right level.

Filters and air pumps can help keep the amount of oxygen in the water at a good level.

On the other hand, a filter is used to clean the water in the fish tank by taking out things like nitrate and ammonia that are bad for the fish.

This will help because if you don’t clean or take care of your fish tank properly, it gets clogged up and hurts your fish.

Feeding And Stocking

To keep your fish healthy and active, you need to feed them enough.

But if you feed the fish too much, they will make more waste when they die, which will make the water smell bad and be toxic.

This can make the fish sick or even kill them.

When it comes to stocking, you might want to keep fewer fish because they leave behind less waste and you won’t have to clean the aquarium as often.

Regular Maintenance

For the fish in the balcony aquarium to be safe and healthy, the tank needs to be checked regularly and preventive measures need to be taken.

If not, the fish tank could get too dirty for the fish to live in over time.

You will have to keep an eye on the fish tank and your fish all the time and do more preventive maintenance on the tank.

Final Words

Setting up a tank outside isn’t that different from setting up one inside. It all comes down to being aware of how the two systems are different and making changes to fit each one.

Without a doubt, your fish will do well if you give them the right support and help along the way.