Can I Put My Turtle Tank by the Window?

One of the big decisions you’ll have to make when adopting a turtle is where to keep its tank. Is a space by the window with lots of sunlight recommended, or is it best to keep a turtle tank in a dark room? It can be difficult to know what the best option is for your pet!

So can I put my turtle tank by the window? While it’s definitely an option to put your turtle tank by the window, keep in mind that algae is likely to grow. It will also be more difficult to regulate temperatures in the tank when it’s placed by the window.

In this article, we’ll go over the two major reasons why it can take some extra effort to keep your turtle tank by the window. We’ll go into detail about temperature fluctuations and algae growth, and we’ll also offer some great solutions for each issue. Plus, you’ll definitely want to take a look at our note on the importance of UV light for your turtle!

A Tank by the Window

There are two main things to remember if you’re thinking about putting your turtle tank by the window. First, the direct sunlight from the window will cause temperatures in the tank to fluctuate. In addition, sunlight encourages algae growth.

Temperature Fluctuations

Turtles are ectothermic, or cold-blooded. This means that they rely on their environment to regulate their temperature, alternating between warm and cold areas in their habitat in order to maintain their body’s ideal state.

This is why it’s so important to provide a reliable heat source with a thermostat, as well as multiple digital thermometers to monitor your turtle tank’s temperature.

Many people really underestimate the power of natural sunlight through a window. It can warm up the water in your turtle tank very quickly! The water can easily overheat, which can then cause problems for your turtle.

Solutions for Temperature Fluctuations

Ensure that the tank has proper ventilation to allow some of the heat to escape. In the wild, the water that a turtle lives in is a lot deeper, which allows turtles to escape the heat and even burrow down into the mud at the bottom of the water.

Sometimes turtles will even migrate to deeper ponds during the warmer seasons. But in captivity, turtle tanks simply aren’t deep enough to allow the same opportunities for your pet to cool off. 

Some turtle owners who have kept their tanks by the window point out that the only way to quickly lower the water’s temperature is to add ice cubes. Constantly adding ice cubes to your turtle tank on a warm, sunny day will definitely take a lot of time and effort, so be sure to remember that when deciding where to place your turtle tank!

One thing you can do to decrease the temperature of your turtle tank is to add background paper to the side of the tank facing the window. While this doesn’t mean that you won’t need to cool the water with ice cubes, it should cut back on how often you have to do so. 

Background paper also tends to help turtles get used to their new environment more quickly. Glass tanks can be confusing to turtles; they don’t recognize their reflections and will often swim into the glass. You can also choose background paper with aesthetically appealing designs, so there are a few plus sides to adding it to your turtle tank.

An additional method of cutting back on the heat from the sun is to add artificial plants to the tank. These can help to block out some of the sunlight, keeping the tank cooler overall. 

Algae Growth

While turtle tanks look great displayed in front of a window rather than in a dark room, there’s another important problem that can (and most likely will) occur: algae growth. This makes it necessary to do frequent full water changes, because the algae will continue to grow and cover all of the tank’s surfaces if you don’t!

Solutions for Algae Growth

The best way to handle algae growth is to stay on top of a strict cleaning schedule. Remember that your goal shouldn’t be to completely get rid of absolutely every speck of algae–that’s an impossible task, since some algae is normal in all turtle tanks. It develops even when the tank isn’t next to a window! 

It’s a great idea to invest in a powerful, high-quality filter for the tank to fight against algae growth. Although it won’t prevent it by any means, it’ll help slow down the process. As far as the cleaning schedule goes, you’ll want to use a small net to remove any waste or uneaten food on a daily basis. 

Every couple of days, use a pH test strip to test the pH level of the tank water. It should typically be between a six and an eight. Algae can have a huge effect on pH levels, so this is an essential step!

For tanks near a window, a full water change may be necessary every week or even more often if algae grows particularly quickly. To clean your turtle tank, make sure not to use regular soap or detergent that you have sitting around the house.

Instead, it’s worth it to buy a cleaner made specifically for turtle tanks; this way you can trust that it doesn’t have any harsh chemicals or dangerous ingredients. 

The first step is to take everything out of the tank, and then knock out any algae and bacteria with your reptile-specific cleaning product. Thoroughly rinse out the tank and leave it open to dry for a few hours.

You’ll also want to carefully clean all tank accessories. If you use substrate, you’ll need to completely replace it as well. Once everything is dry and back in place, you can return your turtle to its home. Always remember to wash your hands before and after cleaning your turtle tank!

A Note on UV Light

You may assume that the direct sunlight coming from the window will not only provide the heat your turtle needs to bask in, but will also eliminate the need for a UV light. This is simply not the case!

When the sun’s rays travel through the window, the UVA and UVB rays that are so important to your turtle’s health are filtered out. Even though it appears that your pet is receiving all the advantages of natural sunlight, the necessary nutrients don’t actually make it through the window.

So if your turtle tank is kept by the window, be sure to provide a UV light and replace it regularly! It’s also important to keep it on for 12 hours during the day and off for 12 hours at night to replicate a normal day and night cycle.

UVA rays maintain bodily functions such as the metabolism, while UVB rays allow for absorption of Vitamin D that helps your pet process calcium. Without sufficient UV light, your pet won’t grow and develop correctly, and it can even develop health issues like metabolic bone disease.

In addition, its immune system won’t function as well as it should, leaving your turtle susceptible to all kinds of problems with its health.

While it’s possible to attain the ideal amount of Vitamin D by giving your turtle supplements, it’s possible for your turtle to overdose on the vitamin. Basking in UV light, however, enables your turtle to take in the perfect amount of these rays.

Metabolic Bone Disease

Metabolic bone disease occurs in animals that have an imbalance of certain nutrients in the body, particularly calcium. Turtles need to have enough Vitamin D in their systems to process calcium, and they get Vitamin D from UVB rays. Because of this, metabolic bone disease is usually found in turtles that don’t have sufficient access to a UV light. 

Common symptoms include swollen legs, bumps along the legs and spine, a softened jaw, and a softened shell. As the disease progresses, you may see your pet begin to walk in more of a jerky manner.

It will also be lethargic and refuse to eat. Unfortunately, metabolic bone disease can be fatal if not treated by a reptile veterinarian. So be sure to get your pet to the vet if you notice any of these symptoms!


If you prefer to put your turtle tank by the window, that’s absolutely fine as long as you’re willing to put in a little extra effort to keep it maintained! First, you’ll want to take temperature fluctuations from the sun into account.

Background paper, plants, and a reliable thermostat are all good solutions. You may also need to use ice cubes if it’s necessary to quickly decrease the tank’s temperature.

As far as algae goes, it’s important to keep the tank as clean as possible. This means changing out the water and cleaning all accessories on a weekly basis. You’ll also need to skim the tank with a net daily to take out any algae floating around, as well as waste and uneaten food.


I’m Devin Nunn, an average joe that just so happens to have a deep love and passion for everything to do with reptiles. Because taking care of them for the vast majority of my life wasn’t fulfilling enough, I decided to begin educating others about them through my articles. read more...