Lizards and Fish in the Same Tank: Is it Possible?

Keeping lizards and fish in the same tank is possible but comes with certain risks. It can also turn into a time-consuming and expensive task.

May 14, 2024By Monika Dimitrovska
lizards and fish same tank possible

While a fish tank isn’t the best enclosure for larger lizards, you can actually keep smaller ones, like bearded dragons, anoles, and leopard geckos, in the same tank as your fish. However, you should first set up the tank correctly.

If you don’t know where to start, keep reading and learn how to create a peaceful home for your lizards and fish in the same tank.

Can You Keep Lizards and Fish in the Same Tank?

fish aquarium
Image credit: PDPics from Pixabay

Both fish and lizards make good pets, and while you can keep lizards and fish in the same tank, you can’t keep just any species in the same enclosure. If you decide to keep your lizards and fish in the same aquarium, you should set it up in a specific way.

Remember that mixing species with different habitat needs and potential predator-prey relationships can result in stress, injury, or even death for one or both types of pets.

Here’s a breakdown of things to keep in mind before setting up your fish tank.


Lizards may see fish, especially fish for a small tank, as potential food because they’re natural predators. Even if you’re considering lizards who don’t eat fish, there’s still a risk, especially if the lizard is hungry and hasn’t been fed.

Additionally, you should choose your fish carefully because there’s a wide range of fish that eat their tankmates.

Habitat requirements

lizard tank
Image credit: Cz XIE from Unsplash

Lizards need basking spots, hiding places, and specific temperature and humidity levels, which may not suit fish. Mixing these habitats can result in stress or health problems for one or both types of creatures.

Water quality

Lizards can produce waste that can degrade water quality very quickly, and as you probably know, if you own fish, they’re sensitive to ammonia, nitrites, and nitrates.

So, keeping lizards and fish in the same tank can increase the waste load and make it hard to maintain a well-balanced freshwater aquarium for the fish.

Risk of injury or disease transmission

Lizards may hurt fish while hunting or exploring the tank accidentally. Additionally, they may introduce parasites or cause common pet fish diseases.

Overall, keeping lizards and fish in the same tank is possible, but we advise against it for the reasons argued above. If you still want to give it a try, keep reading.

How to Build a Successful Fish and Lizard Tank

fish swimming aquarium
Image credit: Cody Wu from Pixabay

First, determine the right size of the tank. Experts recommend a minimum of a 20-gallon tank for most lizards. This size ensures ample space for their comfort and well-being.

Avoid using smaller tanks, except for tiny lizards like baby swifts. A 15-gallon tank could be suitable for smaller lizards.

Note: Salamanders and lizards aren’t the same, but most people don’t know this. If you place salamanders and fish in the same tank, they may kill each other.

Step 1: Gather necessary supplies

You’ll need:

  • Fish tank or aquarium (the bigger, the better)
  • Two large tubes of aquarium glue
  • Twenty or more pieces of slate (5 inches long, 1/2 inch thick)
  • Tank hood with a fluorescent light fixture
  • Filter, heater for lizards, submersible fish tank heater, thermometer, and gravel

Step 2: Prepare the tank

lizard sitting tank
Image credit: Diana Soto from Pixabay

Draw a removable straight line on the exterior glass of the tank around one-third of the way up from the bottom. This line will divide the water area from the lizard habitat.

Lay the tank horizontally, with the top facing you. Then, glue slate pieces in a zig-zag pattern along the line you drew. Ensure they’re level and spaced enough for lizards to move between them comfortably but not too close to allow escape.

Once the adhesive dries, repeat the process on the remaining three sides of the tank. Additional sealant will reinforce the bond between the glass and slate.

Step 3: Tank setup and maintenance

gecko fish aquarium
Image credit: Christine Sponchia from Pixabay

Fill the tank with water up to the level of the main slate pieces. This level will serve as the swimming area for fish. Cycle the tank for a healthy environment for your fish and allow the tank to sit with water for some time before introducing fish.

Now, let’s discuss some essential tips for first-time fish owners. You should clean the tank regularly and monitor water quality, temperature, and signs of distress, especially if you notice strange fish behaviors.

Step 4: Ensuring lizard safety

pet lizard aquarium
Image credit: Hexandcube from Unsplash

Check if the setup allows your lizards to swim back to the slate if they become wet. Don’t obstruct their path with heating cables or air hoses.

Additionally, ensure the stability of the slate attachments. However, don’t touch them all the time because they should remain secure for several years.

You should also provide resting areas for your lizard; add cork bark floating platforms or smooth surfaces for them to climb out of the water.

Regularly inspect and adjust the tank setup to make sure that both lizards and fish live comfortably.

Step 5: Additional considerations

white orange fish swimming fish tank
Image credit: ImsoGabriel Stock from Pixabay

Check water quality regularly because lizards produce waste that can affect the water. We suggest using a substrate suitable for aquatic environments for easier cleaning.

Furthermore, you should install a heater specifically designed for lizards and make sure it’s securely attached to a thick-sided slate to prevent any accidents.

Finally, customize the setup based on the specific needs of your lizards and fish. That way, you can live in harmony with your fish and lizards for many years to come.

Final Tips

gecko tongue tank
Image credit: Peter Law from Pixabay

Both lizards and fish make fantastic pets, and hopefully, our guide can help you create a peaceful home for your lizards and fish in the same tank.

Suppose you still haven’t bought fish. In that case, we suggest getting low-maintenance fish for your aquarium or small community tropical fish that won’t pull lizards underwater and lizards comfortable in water that won’t attack your fish like leopard geckos.

Neon tetras, Corydoras, bettas, and guppies, as well as certain danios, can happily live alongside lizards,and colorful frogs. Avoid freshwater tank cleaners like goldfish as well as silver dollars, knifefish, and cichlids, as they’re not suitable.

Best of luck!

Monika Dimitrovska
By Monika Dimitrovska

Monika is a pet enthusiast and seasoned copywriter with a tech degree. She loves writing, but her heart belongs to her two mixed dogs, Buba and Bono, a mother-son duo. Bono’s siblings found loving homes, sparking Monika’s advocacy for neutering and deepening her curiosity about animal care.

But Monika’s pet family doesn’t end there. She also has two cockatiels and two rescue cats, proving her home is a haven for creatures big and small.