Home » Can You Keep A Tortoise in A Fish Tank or Aquarium?
can you use a fish tank for a tortoise?

Can You Keep A Tortoise in A Fish Tank or Aquarium?

Last Updated on February 19, 2023 by Samantha Harris

Avoid keeping tortoises in fish tanks or aquariums because they lack space, have poor ventilation, retain bad odors, and lead to bacterial growth.

Tortoises grow distressed by the high glass walls and confused by their reflection. Also, it’ll be hard to maintain a temperature gradient (a heated basking area and a cooler side).

It’s more sensible to get a spacious tortoise enclosure as the wooden walls will keep the tortoise from becoming stressed and anxious while keeping it safely contained.

Enclosures make attaching lights and heat lamps significantly easier. Also, wooden enclosures are easy to clean and promote proper airflow, keeping pet tortoises strong and healthy.

Can You Use a Fish Tank for A Tortoise?

Even the largest glass fish tanks will be too small and poorly ventilated for tortoises. Also, bigger tanks are difficult to maintain and transport.

Tortoises require significant floor space to explore and forage. However, the sides must be high enough so the tortoise can’t escape by crawling or climbing over them.

A large glass tank fixed in place may seem like the ideal solution. However, maintaining temperatures for a tortoise in a glass tank is difficult as glass loses heat.

Also, there won’t be enough room for a thermal gradient so that the tortoise can adjust its temperature.

Tortoises prefer non-transparent walls and will feel vulnerable and exposed in glass-sided aquariums. They’ll attempt to get through the glass panes, so you may find a tortoise pacing back and forth.

Can You Put a Tortoise in A Fish Tank?

Keeping a tortoise in a fish tank isn’t recommended. Fish tanks are made of glass, which absorbs and traps heat, making it hard to maintain an even temperature.

Also, air and gas exchange is reduced, leading to respiratory issues and poor shell and skin health.

Most tortoises grow to be 10+ inches, so they need room to forage and explore to avoid getting stressed, irritable, bored, and depressed.

Fish tanks provide one temperature across the entire space, although glazing gradually loses heat.

Tortoises are ectothermic, relying on their environment to regulate their body temperature. So, they need to change their position when they get too hot or cold.

In fish tanks, the glass walls are high, making it difficult to attach the necessary lighting in the right positions. Tortoises must absorb UV rays to synthesize vitamin D, which is needed to absorb calcium.

Can You Keep a Tortoise in An Aquarium?

You may wonder if an aquarium is more suitable than a fish tank. In truth, there’s no real difference between the two regarding their suitability for tortoises.

Aquariums, like fish tanks, are made of glass and pose the same issues, such as:

Poor Ventilation

If you put a cover on an aquarium with the tortoise inside, it’ll run out of oxygen and die from suffocation.

Aquariums work for fish because they have gills and derive oxygen from the water. An oxygen pump is almost always necessary in these cases.

Adding water to the tank will kill a tortoise because it can’t swim or breathe in water. Tortoises aren’t like turtles, so they don’t need a water pool in their tank.

The air will circulate a little, but it’ll grow stagnant. Since tortoises need a warm environment, basking areas turn into breeding grounds for germs, bacteria, fungi, and parasites.

can you keep a tortoise in an aquarium?

Build-Up of Bad Smell

That limited circulation means unpleasant odors and bacteria will build up.

Ammonia will build up in the aquarium when the tortoise produces waste. The smell of ammonia can be reduced with proper ventilation, but that’s less likely to happen in an aquarium.

The excess ammonia, especially as it ages, will aggravate the tortoise’s respiratory system, leading to respiratory infections. Regular spot-cleaning reduces the smell, but not entirely.

Maintaining Humidity

According to the Journal of Thermal Biology, humidity affects how tortoises digest food.

Aquariums make it difficult to maintain a consistent humidity level. Although many tortoise species are accustomed to dry locations, they don’t fare well when humidity levels fluctuate significantly.

Too much humidity can cause shell rot, while too little humidity can make shedding skin difficult. Oscillating between ranges can lead to illness, lethargy, and depression.

The standard aquarium lids trap air inside, resulting in a greenhouse effect when you fill a water dish. Although screens can assist, ventilation limitations can still lead to humidity concerns.

According to the Journal of Zoology, this can lead to reduced activity and behavioral problems.


Tortoises have good memories, so they’ll soon become bored of walking back and forth. They want to explore new terrain and search for food and water like in the wild.

Anxiety And Distress

No tortoise has passed the mirror test, which scientists use to determine whether an animal can recognize itself in a mirror. This is relevant to a glass tank or aquarium, as glass is a reflective material.

Tortoises roam their territory and expand their foraging areas, so a glass enclosure will cause agitation. They can see the outside and want to explore this area, but they encounter an invisible barrier.

Glass is incomprehensible to tortoises, so they attempt to reach the new and interesting location but repeatedly bump into the illusory glass wall.

Also, a tortoise will mistake its reflection for another tortoise, resulting in stress and aggression. A tortoise will think there’s competition from another male for limited territory and resources.

Lack of Exercise

A lack of space makes it more difficult for tortoises to get the exercise they need to stay healthy. While tortoises are slow-moving animals, they still need to walk, dig, and climb.

Limited Space

Terrestrial animals like tortoises like to wander and explore their surroundings. They require enough floor space to allow the pacing behavior they’re accustomed to in the wild.

It can be difficult (and expensive) to find a large tank to adequately house a tortoise, and even smaller species need a relatively large enclosure to roam.

While using an old fish tank or acquiring a second-hand aquarium online may seem like the perfect home for a tortoise, they have various drawbacks. A tortoise needs a spacious wooden enclosure.