The water in a turtle’s tank may become murky for various reasons.  We will discuss the potential causes of a cloudy tank, how to fix cloudiness, and prevent it in the future.

In this guide, you’ll learn:

  • What causes a cloudy turtle tank?
  • How to fix cloudy turtle tank water
  • How to prevent cloudy water in the future
Featured image showing turtle swimming in cloudy water

Turtles are generally very messy compared to other reptiles; therefore, there can be various reasons for a cloudy tank. Many assume the sure way to fix a cloudy turtle tank is to replace the water. However, this may sometimes hinder rather than help the water quality.  

Key Takeaways

Cloudy turtle tanks can be caused by several factors, including algae growth, bacterial blooms, and sub-optimal water pH levels. To prevent these issues from occurring, it is essential to:

  • Keep your tank out of direct sunlight.
  • Use a high-quality filter.
  • Perform regular water changes.
  • Clean your filter media regularly with aquarium-safe products.
  • Avoid overfeeding your turtles.
  • Test your water regularly using a reliable aquarium testing kit.
  • Take steps to adjust any imbalances in the tank’s water if necessary.


If you recently changed your turtle’s water, leave the water alone and let the tank establish. It could take days and sometimes a couple of weeks, but the tank will usually fix itself. Sometimes the best thing to do is nothing at all!

What Causes A Cloudy Turtle Tank?

The three most common causes of a cloudy turtle tank:

  1. Poor filtration
  2. Excess algae growth
  3. Bacterial blooms
  4. Unbalanced pH

Poor Filtration

Poor filtration is a common cause of cloudy tank water. Without adequate filtration, debris and waste can build up in the tank, causing cloudiness. Therefore, it is essential to use a high-quality filter specifically built for turtle tanks. These come with enough filter media to keep your tank clean. 

Excess Algae Growth in the Tank

Algal growth is another common cause of cloudy turtle tanks. Algae in your tank can be caused by the following:

  • Too much light 
  • An imbalance in nutrients
  • Poor filtration

Keep your tank out of direct sunlight and use a high-quality filter to prevent algae from overgrowing. You should also perform regular water changes to remove excess nutrients that could lead to algae growth.

Bacterial Blooms in the Filter

If the cloudiness in your tank water is milky white in color, it is probably caused by a bacterial bloom. Bacterial blooms occur when your tank’s microbiome community is just being established or is getting disturbed. This usually happens when you change your water. During this period, there’s an imbalance in the bacteria colonies present. This causes the bacteria to reproduce rapidly, resulting in cloudy water and a smelly odor in your tank. 

Most of the bacteria present in turtle tanks are beneficial. These “good” bacteria help regulate pH and ammonia levels in your tank. In most cases, the cloudiness will eventually disappear after a few days as the bacteria settles and returns to a balanced level. 

Unbalanced pH levels

The pH level affects how well certain substances dissolve in the tank water. Undissolved substances can affect the efficiency of filters and other cleaning methods, such as gravel vacuums or siphons. Bacteria can also overgrow if pH levels are off since certain bacteria thrive at different pH levels.

Therefore, it is crucial to regularly test and adjust pH levels using reliable testing kits to maintain dissolved substances and bacteria at optimal concentrations to keep your turtle healthy in its environment.

Now that we understand the causes of cloudy turtle tank water, we can move on to fixing this problem.

How to Fix a Cloudy Turtle Tank

Clean the Tank and Filter Regularly

The first step in fixing a cloudy turtle tank is to clean it regularly. This means removing debris such as uneaten food and other organic matter, using a net, and cleaning the filter. Use an aquarium-safe cleaner when cleaning your turtle tank, as some can be harmful to turtles. 

In addition, filter media should be replaced every few months to ensure that it maintains its efficiency in filtering out particles from the water. 

Adjust Feeding Habits

Ensure that you are not overfeeding your turtles. Feed them only what they need daily, and remove any uneaten food after 10 minutes, so it doesn’t start decomposing in the water and clouding up your tank.

Test and Balance Water pH Levels.

Water pH levels are essential for keeping your turtle’s tank water clean. You should test weekly using an aquarium test kit that usually contains a sensor or paper strips you can use to easily measure the tank’s pH. 

If the pH levels are off, it can cause cloudy water in a turtle tank because certain bacteria thrive at different pH levels than others. Dissolved substances and water quality are also affected by pH levels.

Adjust the pH accordingly with buffers until you reach the recommended level of 7-8.

In summary, maintaining a clean tank and filter, adjusting feeding habits, and testing and balancing pH levels are vital in keeping your turtle’s tank water clear. 

Now that we’ve discussed how to fix cloudy turtle tank water let’s look at ways to prevent it from happening in the first place.

Tips for Maintaining Clear Turtle Tank Water

Here are a few steps to help keep your turtle’s home clean and in top condition.

Use High-Quality Filters and Media

Since turtle tanks can quickly become dirty, the filter is a critical component of any turtle tank. Make sure to use a high-quality filtration system explicitly designed for turtles. 

Look for filters with comprehensive filtration capabilities that include particle filtration and bio-filtration. You can also use other filter media, such as activated carbon or zeolite, to help remove impurities from the water.

Monitor Feeding Habits Closely

Overfeeding can increase waste products like ammonia. Make sure to feed your turtles appropriately by monitoring their feeding habits closely and then adjusting the amount of food to avoid creating excess waste. 

You should also avoid feeding them processed food or treats too much. These can contribute to poor water quality due to extra nutrients in the tank.

Change your Tank water

You should regularly change your tank water every week or more often if needed. This helps reduce the buildup of toxins and maintain a good balance in the pH, bacterial community, and dissolved substances of the tank’s water.

When performing water changes, replace just part of the water, keeping about 25-30% of the old tank water. This prevents your pets from experiencing shock due to sudden changes in the water parameters, such as temperature. It also helps maintain pH levels and the established bacterial balance.

Gradual water changes will also prevent bacterial blooms from occurring by keeping the balance of bacteria in your tank.

These tips can help keep your turtle’s tank water clean and clear. Now let’s look at the importance of regular maintenance for a healthy aquatic environment.

Benefits of Keeping a Clean Turtle Tank

Here are some of the benefits that come with keeping a clean turtle tank:

Improved Health for Turtles

Regularly cleaning your turtle’s tank can help to keep its environment free from harmful bacteria and other contaminants. This will ensure they have access to fresh, oxygenated water necessary for their overall health. Additionally, regular cleaning can prevent excess algae growth in the tank, which can be toxic if ingested by turtles.

Better Aesthetics for Home Decor

Keeping a clean turtle tank improves your pet’s quality of life and adds aesthetic value to any home decor setting. In addition, a well-maintained aquarium or terrarium looks terrific as part of any room design and provides an attractive focal point that visitors will appreciate.

Reduced Risk of Disease and Parasites

Dirty tanks are breeding grounds for parasites such as worms, mites, fungi, protozoa, etc., all of which pose severe risks to your pet’s health if left unchecked. Regularly cleaning out debris from the bottom substrate and replacing dirty filter media helps keep these organisms at bay while providing a safe habitat for your turtle.

Though turtles may not be as sensitive to dirty tank water as fish, their quality of life is definitely better with a cleaner tank. As a bonus, your turtle will hardly ever get sick, which can help save on additional care costs.

Overall, it is crucial to maintain a clean turtle tank both aesthetically and functionally to ensure optimal living conditions for your pet turtle and prolong its life.

Keeping your turtle tank clean can help ensure your reptile companion’s health and well-being.


Cloudy tank water is a common issue for turtle owners. Knowing the causes of this problem and how to fix it is key to keeping your pet’s environment healthy and safe. 

Prevention is always best, so these tips and techniques will help you keep dirty tank water at bay. With the proper knowledge, you should be able to promptly fix your turtle’s cloudy tan water so that your pet has a clean and comfortable habitat.

If you have a cloudy turtle tank, taking quick action is vital since dirty water can lead to health issues for your pets. Thankfully, there are several steps that you can take to clear up the murky water and get back on track with proper reptile care! ReptileKnowHow is here to advise you on how best to fix cloudy turtle tank water, so your beloved pet remains healthy and happy.


Why is my turtle tank water cloudy?

It could be related to several factors, but the most common is either due to bacteria bloom or overfeeding. Try waiting several days or even a couple of weeks. Often, the water will fix itself if the cloudiness is bacteria-related because of a recent water change.

How can you reduce cloudy water?

Avoid overfeeding your turtles or try feeding them outside their enclosure to reduce cloudy or murky water from developing.

How often should you clean your turtle’s tank?

We recommend a 20% water change each week and 80% change each month.

Lara Sotto

Lara Sotto

Lara Sotto is a marine biologist, freelance animal writer, and reptile lover. She is passionate about empowering reptile owners with the information they need to give the best care possible for their reptiles. She is currently taking up her Ph.D. in Marine Science and providing her knowledge to the ReptileKnowHow community.

16 thoughts on “How To Fix Cloudy Turtle Tank Water”

  1. I cleaned my tank, and all the rocks, pebbles and rocks backings. All cleaned, I replace the rocks and all, but when the water splashes from the filter, I used squeegee to clear the drops, but the there is a film left on the sides. How do I keep these sides clean without looking dirty. I wabpnt to keep the sides clean. Don’t know what to do. Please give me some suggestions.
    Thank you for all your help.
    Is there something for use to keep the insides clean.

    • Honestly, I think the only thing you can do to reduce splashing is to raise the water level or be diligent about cleaning the glass with a damp paper towel or something.

      Unfortunately, there is no real cure-all for that particular problem.

      Sorry I couldn’t help more!

  2. Thanks for posting this article. We have had a maps turtle for 21 years. He is 8 1/2 inches long and feeds on pellets, hand fed no less. We recently moved him to a 40 gallon tank and run 2 – TopFin 70 filters. We also have 14 goldfish in the tank with him. The goldfish constantly nibble at his shell and flesh. The water remains clear but has a constant brownish color, so it doesn’t look clean. I replace the filter media regularly, use TopFin Water Conditioner to remove tap water chemicals and TopFin Biological Cleaner to help breakdown waste. I also replace 25% every three weeks. From your article, I am now suspecting I’m messing with the water too much?? Your comments and thoughts would be much appreciated.

    • 14 goldfish is quite a few for a 40-gallon tank plus a turtle!

      I would recommend finding someone with a pond to re-home the goldfish and only keep a few or to rehome them all and replace them with feeder guppies, which have a much lower bioload. That, or consider upgrading the tank.

      The brownish water is likely due to the heavy amount of bioload in the tank (waste from the turtle and all of the fish). I would almost argue the water isn’t changed enough actually.

      I hope this helps!

  3. We’ve had 2 red eared sliders for about 4 years now and the tank has just started getting cloudy. We keep around 30 gal of water in it and clean it about every 2 to 3 weeks. We feed them in the tank and have never had this problem except for a few hours after cleaning, never lasting more then a day and not that often.
    Appreciate any help

    • Hey Rusty,

      Two Red Ear sliders in 30 gallons is a bit tight. We’d recommend upgrading the enclosure size to help with these issues. Cloudy tank water is usually caused by bacteria blooms. We see this happen if people clean their tanks too often or change 100% of their water at a time. You can also try feeding your turtles in a separate enclosure.

  4. Thank for all this terrific information. So I found your article several weeks ago, about a week after I had changed all the water in my red earred slider tank. So I waited as you instructed. It’s now been 5 weeks since I’ve changed his water. Should I be waiting longer or is there something else that’s wrong. I also changed his filter every other week. Thanks again!

    • Hey Jan,

      So water changes I would argue are actually more important than cleaning out and replacing your filter. Water changes should be done weekly or biweekly depending on your nitrate levels (water changes are done to remove nitrates from the water).

      If you don’t know your nitrate levels, consider getting a water test kit, otherwise while waiting for the tank to cycle, you’re not exactly sure when it’s done and taking a shot in the dark. I would replace the water 20% every week or so to be safe (though initially, I would change 50-75% now that it’s been 5 weeks). The water changes won’t eliminate your bacteria, cleaning the biological part of your filter (this is usually a plastic piece or rocks or something) will (but NOT the sponge part that catches the waste and material, that can be rinsed problem-free!).

  5. Hi, I recently got a baby yellow belly slider. I just finished setting up the tank and it has just spent its first few days in the tank. But the water is cloudy, and I know I’m supposed to wait it out but it seems to be getting worse. I was wondering if this is normal or if I should try to rebuild the whole tank.

    • Hey there! You can do partial water changes of around 10-20% per week, but do not clean the filter and try to wait things out! It can take up to a month for things to cycle properly.

  6. Hi! I have a red-eared slider and am performing pH checks weekly along with partial water changes. I’m just beginning to cycle the tank, and while there is a lot of information out there, I’m not finding specifics. If I see the ammonia raise, I would expect pH to also raise- so should I lower this pH and with what? (Is sodium carbonate OK for raisinging and acetic acid OK for lowering?) Or should I leave it alone and wait for it to stop as the nitrites and nitrates should then increase?

    Sorry, it’s a lot of questions. Thank you for your time if you are able to respond! I appreciate your website!

    • Hello! It’s great to hear that you’re taking good care of your red-eared slider and monitoring the pH of the tank. In terms of cycling the tank, it’s normal for ammonia levels to rise initially as beneficial bacteria begin to grow and break down organic waste. As the bacteria grow, they will convert the ammonia into nitrites and then nitrates, which are less harmful to your turtle.

      Regarding your question about pH, it’s important to note that while ammonia can increase the pH of the water, it’s not always the case. In fact, in some cases, the opposite can happen and the pH can decrease. That being said, it’s generally not necessary to adjust the pH during the cycling process unless it becomes very extreme (below 6.0 or above 8.0).

      If you absolutely do need to adjust the pH, it’s important to do so slowly and gradually to avoid shocking your turtle. Sodium carbonate can be used to raise the pH, but it’s important to use it sparingly and monitor the pH closely. Acetic acid can be used to lower the pH, but again, it’s important to do so very gradually and monitor the pH closely. It is difficult to provide you with more specific advice without seeing the enclosure and test parameters.

      In general, it’s best to let the tank cycle naturally and wait for the beneficial bacteria to establish themselves. This can take anywhere from a few weeks to a few months, depending on various factors such as the size of the tank, the number of animals, and the amount of organic waste being produced. Keep up with your weekly pH checks and partial water changes, and be patient as the tank cycles. Make additions to change pH only if if is clearly going outside of safe ranges. I hope this helps!

  7. Hello my name is Kellyann my turtle tank seems to get cloudy fast. I bought Clear Water a product made by Jungle . Can I use this ?

    • Hi Kellyann,

      Cloudy water in a turtle tank can be caused by various factors such as overfeeding, improper filtration, and lack of regular water changes. Using a product like Clear Water by Jungle may help, but it’s best to address the root cause of the cloudiness to prevent it from reoccurring.

      Here are some simple steps to help fix the cloudy water in your turtle tank:

      • Reduce feeding – Overfeeding your turtles can cause an excess of waste and leftover food in the tank, leading to cloudiness. Feed your turtles only what they can eat in a few minutes and remove any uneaten food promptly.
      • Increase filtration – Ensure that your filter is adequate for the size of your turtle tank and that it is working correctly. Consider adding additional filtration if needed.
      • Perform regular water changes – Regular water changes are essential for maintaining water quality in your turtle tank. Aim to change 25% of the water every week, depending on the size of your tank.
      • Clean the tank regularly – Use a siphon or gravel vacuum to remove debris from the bottom of the tank during water changes. Also, wipe down the sides of the tank to remove any algae buildup.
      • Use a water clarifier – If the above steps do not clear the water, you may consider using a water clarifier like Clear Water by Jungle. Follow the product instructions carefully and continue to address & find the root cause of the cloudiness – it could be that you need to allow the growth of enough beneficial micro-organisms to process the waste in the water.

      I hope this helps, and good luck with your turtle tank!



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Lara Sotto

Lara Sotto

Lara Sotto is a marine biologist, freelance animal writer, and reptile lover. She is passionate about empowering reptile owners with the information they need to give the best care possible for their reptiles. She is currently taking up her Ph.D. in Marine Science and providing her knowledge to the ReptileKnowHow community.

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