Estimated reading time: 6 minutes
Reptiles come in all sorts of shapes and sizes and can be outstanding low-maintenance pets.
However, reptiles like some dragons and snakes can grow very large, and not everyone can dedicate an entire living room wall to their reptile.
Fortunately, many species stay small for life and can live comfortably in a 20-gallon enclosure or less!
What is Considered a “Small Enclosure”?

Here at Vision Products, the most compact enclosure we offer is a 20-gallon reptile enclosure.
However, many consider a 10-gallon tank to be the smallest option for a reptile pet.
Anything smaller than a 10-gallon tank would make it difficult to include decor like a substrate, water and food bowl, plants, and more, while also leaving space for your pet.
That being said, here are 5 of our favorite reptiles who live happily in smaller enclosures.
5 Pets for 20-gallon Reptile Tanks
1) Leopard Gecko

Adult Length:
- Females: Up to 8″
- Males: Up to 11″
Behavior: Terrestrial
When people look to adopt a small reptile pet, leopard geckos are often the first that come to mind.
These geckos are very docile creatures, live primarily on the ground, and their space requirements are very reasonable.
A 20-gallon reptile tank will provide plenty of room for this small reptile pet. Leopard geckos will also find comfort in a smaller 10-gallon enclosure, even after including decor and other equipment.
But keep in mind, because they’re terrestrial, the length of the enclosure will be more important than the height.
2) Green Anole

Adult Length:
- Females: Up to 5″
- Males: Up to 8″
Behavior: Terrestrial
Even smaller than leopard geckos, green anoles make fine pets for small reptile tanks.
Not only are they small and fun to watch, but they’re also intelligent, easy to care for, and very friendly.
In fact, my old kindergarten teacher had two green anoles in a 20-gallon tank in our classroom.
Once a month she would sit us down and let the anoles walk around and say hi to us… Fearless little lizards, they were.
You may be reluctant to bring your anole around a group of kindergarteners, but make no mistake, they are excellent pets for all ages.
And they will live very happily in a 10 or 20-gallon enclosure!
3) Crested Gecko

Adult Length (With a tail*):
- Males: 10″ – 16″
- Females: 10″ – 16″
Behavior: Arboreal
Another popular reptile that comes to mind is the crested gecko.
These pets are docile, generally easy to care for, and have very active personalities.
They’re a little larger than the previous lizards, so 20 gallons is the minimum size tank for an adult crested gecko (A 10-gallon tank will work for younger/smaller geckos).
Also, crested geckos are arboreal and love to climb so you need to prioritize the height of the tank over the length.
You should also include elevated surfaces, branches, and foliage for the ideal habitat.
*Some lizards can intentionally detach their tails from their bodies to distract predators. After a lizard “drops its tail”, a new one typically grows in its place.
A crested gecko, however, can drop its tail but it will never grow back. This isn’t harmful to them, but many adults are shorter in length because of it (tails are usually 4 to 6 inches long).
4) Rosy Boas

Adult Length:
- Females: Up to 36″
- Males: Up to 24″
Behavior: Terrestrial
Rosy boas are relatively small snakes, typically reaching a maximum length of 3 feet (males are typically smaller, around 2 feet).
They’re also docile, easy to care for, and spend a lot of time burrowing, which makes them good snakes for beginners and a good option for a relatively small enclosure.
For a hatchling, a 10-gallon tank will work just fine.
Then, as a male rosy boa grows into adulthood, he will find comfort in a 20-gallon enclosure.
Females, on the other hand, have longer bodies and may need a little more space, like a 30 – 40 gallon tank.
Regardless of the enclosure size, you should prioritize the length over the height because the rosy boa is a terrestrial, slow-moving snake that likes to burrow.
5) Kenyan Sand Boa

Adult Length:
- Females: Up to 32″
- Males: Up to 15″
Behavior: Terrestiral
The size of your Kenyan Sand Boa’s enclosure is determined by several factors, including the snake’s age, size, and activity level.
Kenyan Sand Boas are relatively small snakes compared to other boas, ranging from around 15 inches as a male to just under 3 feet as a female.
They’re also terrestrial and not very active snakes, so an elaborate setup isn’t necessary, but you should include a deep, soft substrate as they like to burrow.
As a general rule of thumb, you should aim for an enclosure that is at least 20 gallons in size for an adult Kenyan Sand Boa. For a hatchling, a 10-gallon enclosure will be an excellent temporary home.
And if you feel your snake should have more room to roam in adulthood, then a 30-40 gallon tank is also a great choice for you.
Wrapping Up
Many amazing reptile pets live comfortably in a 20-gallon reptile enclosure, like geckos, anoles, and smaller snakes.
That being said, you should always research your specific pet.
Is your new reptile arboreal and frequently active? Is your snake growing larger than you expected? Do you simply want your pet to have more space, regardless of its size?
Take as many factors into consideration as you can. This way you can offer the best enclosure, whether that’s a 10-gallon, a 100-gallon, or anything in between!