You might be surprised by how many different species can live peacefully for their entire lives in a tank this size, even if 40 gallons may not seem like much space.

There are many options available, whether you choose a reptile that is simple to handle or a really active pet that you can watch run around the area.

The Blue-Tongued Skink, Corn Snake, Spiny Tailed Lizard, Gargoyle Gecko, Kenyan Sand Boa, and Veiled Chameleon are a few of the top choices for a 40-gallon tank.

If you want to avoid having to upgrade to a larger tank in the future, what 40-gallon tank should you choose? We’ll go through the requirements for each of these six reptiles in detail so you can choose which is best for you.

First-Tongued Skink
A interesting tiny lizard with lots of personality is the blue-tongued skink. The northern blue-tongued skink and the Indonesian blue-tongued skink are two of the blue-tongued skink species available.

On average, northern skinks are a little tougher. A common color variation or an uncommon morph are both options.

When properly cared for, this long-lived skink can live for 15 to 20 years or longer. The northern blue-tongued skink can reach lengths of up to 24 inches.

They won’t have any problems living their entire lives in a 40-gallon tank because they aren’t particularly active. Until they become larger, young skinks can be housed in a 10 or 20-gallon tank.

Choose a terrarium that is long rather than tall since these terrestrial lizards prefer floor space. You can keep ladies in pairs or groups, but you could think it’s safer to keep one person by themselves.

If you have multiple skinks in the same enclosure, keep a close eye out for signs of fighting.

The temperature difference between one side of the tank and the other should be between 75 and 82 degrees for these skinks to thrive.

There should be a 90–100 degree basking area at the heated end as well. Although full-spectrum lighting may not be required for these skinks, it is advantageous to them.

These resilient lizards can eat a variety of things. They are omnivores who thrive on a mixture of fruits, vegetables, and insects. They are among the few reptiles available that can thrive without having access to live insects.

They can consume cooked meat, thawed pinky mice, hard-boiled eggs, cooked insects in a can, and very high-quality wet or dry dog or cat food.

They will eat just about any fruit or vegetable, but make sure it is free of pesticides.

2.Corn Snake 
The corn snake may be the ideal snake for you if you want a large, intriguing snake with vibrant colors that is very simple to care for and only requires a 40-gallon terrarium.

Despite being one of the most common snakes sold as pets, don’t assume that since they are so widely available they are uninteresting.

The color and pattern variations of corn snakes are among the broadest of any snake species.

This is a snake that you can take outside and handle without having to dedicate a lot of space to its terrarium because they grow quite large—up to 5 feet—and often accept handling with no trouble at all.

If properly cared for, these long-lived snakes can live up to 20 years, and they are quite simple to breed.

Although being in a room with natural light will help them to have day and night cycles as well as seasonal cycles, they don’t require any special lighting. The temperature gradient in their terrarium should be from the low 70s to about 85 degrees.

3. the urethra (Spiny Tailed Lizard)
The Uromastyx might be the ideal lizard for your 40-gallon tank if you’re seeking for something distinctive.

There are roughly 18 different kinds, and each has benefits and drawbacks related to keeping them as pets. Any of these species is a good choice for a 40-gallon tank because the majority of species grow to a length of between 10 and 18 inches.

Since these lizards are diurnal, you can enjoy seeing them at any time of day. They prefer a long tank over a tall one because they like to graze on vegetation and dig.

The tank should have very strong lighting, an 80 to 100 degree temperature gradient, and a basking zone that is at least 120 degrees.

The terrarium doesn’t typically need to be heated at night. Your Uromastyx should have access to enough substrate.

Having hiding spots is crucial if you choose an enclosure without substrate that can be borrowed in. The fact that this strange reptile mainly consumes green plants might be a significant benefit for many keepers.

4.Gargoyle Gecko 

The gargoyle gecko is an interesting and unusual choice if you’re looking for a reptile that will thrive in a 40-gallon tall tank and is a terrific choice for a planted terrarium.

These geckos thrive in terrariums with lots of live plants and vines since they prefer to be in the trees. They only reach a maximum length of about eight inches, which makes them really entertaining to watch move about in your tank.

You may maintain a male and many females in a 40 gallon tank to establish a colony. It’s important to remember, though, that geckos often snare one other’s tails.

No. 5African Sand Boa
Although the natural color morph is pretty lovely, there are many more color options available.

These little boas barely reach a maximum length of 2 feet, and males are considerably smaller, typically only reaching 20 inches. This small snake has a lengthy lifespan, occasionally lasting for more than 30 years in captivity.

These snakes can live in terrariums up to 40 gallons in size, but they will like the extra space and you can maintain one male with one or two females.

You’ll need a long tank rather than a tall one because these snakes are terrestrial burrowers. It’s a good idea to provide a substrate that allows for burrowing in order to fully enjoy your boas’ behavior.

Avoid any large rocks or wood pieces that could fall on them and injure them because they will burrow deeply. They usually don’t seem to be interested in climbing, so a cage made only of substrate and a few thin pieces of wood for ornamentation should be adequate.

The preferred temperatures for Kenyan sand boas’ basking areas are around 95 degrees and 80 degrees on their cooler sides. It is fine to let the enclosure’s temperature fall to the mid-seventies at night.

When they are young, these boas often perform best with live pinky mice, but as they become older, they are content to accept thawed frozen mice. It’s ideal to provide food about once each week. It’s a good idea to feed your cagemates separately in order to prevent competition.

6.Veiled Chameleon 

Are you looking for a particularly eye-catching resident for your 40-gallon tank? Chameleons require a screen-sided habitat because they require more ventilation than many other kinds of reptiles do.

However, you can simply set up a screen enclosure for your chameleon that takes up about this much space if you are setting up an enclosure expressly for the reptile you desire and need an enclosure that can occupy the same size as 40 gallons.

If this is your first chameleon, veiled chameleons are among the species that are most resilient. The veiled chameleon is now far more hardy in captivity thanks to captive breeding than the previously available wild-caught specimens.

These lizards grow rather large, up to two feet long when fully grown, but they move slowly and have few space requirements, so they can survive just well in a cage that holds around 40 gallons.

When left alone, they thrive. Veiled Chameleons thrive in a densely planted, tall rather than wide terrarium.

As your chameleon grows, it’s a good idea to keep increasing the size. The ambient temperature in the rest of the cage should be between 72 and 80 degrees, and the veiled chameleons require a basking light that maintains an area between 85 and 95 degrees.

As long as the temperature does not go below the mid-forties, a nightly dip is a fine option.

The greatest meal for chameleons is live food, and crickets are a fantastic choice. Watching your veiled chameleon consume bugs is a lot of pleasure.