How To Lower Humidity In A Reptile Tank

how to lower humidity in a reptile tank

Some people prefer warm weather while others prefer cold weather!  Animals have thier preferences too.  Beyond preferences, reptiles have pretty specific sets of conditions they need in order to survive and thrive.   These environmental needs include lights, temperature, and humidity!  Unlike with a pet dog, you need to pay close attention to the humidity in your pet reptile’s enclosure.   So, how do you get rid of humidity in a reptile tank when there is just too much?

Here are some quick tips on how to lower humidity in a reptile tank:

To lower humidity in a reptile tank, you should make sure there is plenty of ventilation and you can even purchase a dehumidifier for the reptile’s room.  Substrate and water supply are important factors that affect humidity levels.  And lastly, you can always throw some rice into your pet’s enclosure to absorb excess moisture.

Let’s talk about humidity now and figure out how to get your reptile’s enclosure just right for them!

How Humid Is Too Humid For a Reptile Enclosure?

Reptiles have very different needs than we do.  So how do you know what humidity a pet really needs?

Luckily, reptiles can be generalized into three main groups.  These groups are organized based on where your pet is found in the wild.  Desert reptiles have the lowest humidity ranges.  Reptiles from temperate areas need a moderate level of humidity.  And of course, tropical reptiles need extremely high levels of humidity.  The chart below will provide you with some exact values.

Reptile Humidity Chart

This chart also provides ranges for some of the most common pet reptiles.  You can see that bearded dragons and leopard geckos need a relatively low humidity level in their enclosures.  These animals are accustomed to the hot dry desert.

But what if an enclosure does get a little too humid for an animal, is the extra moisture a bad thing?

Why High Humidity Levels Can Harm Your Pet.

Unfortunately, if your desert reptile lives in a humid environment, it might become sick!

High humidity levels can cause respiratory infections in reptiles that aren’t suited for the moisture.  Respiratory infections are dangerous for reptiles.  They have many symptoms associated with them such as lethargy, difficulty breathing, and loss of appetite.  Respiratory infections require a vet visit as they can be hard to diagnose and treat.  For some reptile owners, the wheeze of a respiratory infection might sound like a normal hiss coming from their pet ball python.

In addition to disease, humidity levels that are too high are also breeding grounds for bacteria, mold, and fungus.  You and your pet will benefit from keeping humidity levels low and under control in many cases.

How Do You Monitor Humidity?

Monitoring humidity is a common practice for reptile owners.

Whether you have a crested gecko that needs 80% relative humidity, or a bearded dragon that only wants about 40% relative humidity, you need to be able to measure it.  Hygrometers are tools used to measure the relative humidity in the air.  These meters can be purchased from most pet and reptile supply stores.  They usually come with a thermometer attached as well.

Hygrometers can be placed throughout an enclosure, to ensure that there isn’t any one spot that is uncomfortable for your scaly friend.

5 Ways To Lower Humidity In A Reptile Tank

Now that you know how humid a tank should be. and how to measure humidity, how can you control it?  How do you make humidity go down in a tank that is too moist for a reptile?

We have 5 foolproof tips below.  Some of them can be initiated immediately, without any large cost or effort.

1. Use The Right Substrate, Or None At All

One of the biggest factors that affects humidity in a reptile tank is the substrate.

Substrate is the material that makes up the bottom of a reptile’s enclosure.  Substrate is a very general term because substrate can be anything from sand to individual pieces of felt.  In the effort to lower humidity, substrate choice is important.

The Great Substrate Debate

If you already own a reptile, you have probably seen a lot of different opinions online about substrate.

Reptiles that need less humidity are a source of a lot of the conflict.  The argument is over whether or not substrate should be used at all for reptiles like leopard geckos and bearded dragons.  In my opinion, there are pros and cons to all substrate types.

No or low substrate can be a great way to keep humidity levels low.  Usually, people who use no substrate or low substrate may just line their reptile’s enclosure with paper.  The pros of this are that humidity stays very low.  Additionally, it’s very easy to clean and change paper substrates.

If you’re on the side of wanting to provide your reptile with substrate, there are anti-moisture options available for you.  Loose sand keeps moisture levels in an enclosure low but can be accidentally ingested and hard on your pet.  Impacted clay sand is a great substrate option.  Impacted clay sand is not loose, so your pet won’t end up ingesting any of it.  It lowers humidity in the tank because it has almost no capacity to hold and retain moisture.

Changing your substrate is a sure way to lower humidity, plus it’s affordable and a quick fix!

Avoid Mulch and Wood Chips

Whether you pick a low or no substrate to keep our tank dry, you will want to avoid mulch, mosses, and wood chips.  These substrates will absorb water in the air but will not lower humidity levels.  Unfortunately, all of these substrates will actually hold onto water and can increase relative humidity levels.

2. Increase Ventilation

Increasing ventilation is a great way to lower humidity in a reptile tank.

If you find that your tank stays too humid, even though the environment outside of the tank isn’t humid at all, you need ventilation.  Some reptile enclosures come with a good amount of ventilation built in.  Horizontal tanks with a mesh top for example should allow for good airflow throughout the tank.  But if you’re struggling with humidity, adding more airflow will help immensely.  More airflow will bring humidity levels down.

Adding ventilation is a DIY undertaking.   The easiest way to add ventilation is to purchase mesh vents and install them yourself.  Check out this video for a proper tutorial.

With more airflow, you should start to see a decrease in the overall humidity of your reptile’s enclosure. Adding ventilation to your enclosure isn’t too expensive, as long as you have the skills and tools needed to make the change.

3. Use A Dehumidifier

Do you live in a tropical or humid area?

If so, you might find that not only is the humidity in your tank a problem, but so is the humidity outside of it!  Pets like bearded dragons are not suited for hot warm Florida-like weather.  Another way to decrease the humidity in your reptile’s tank is to lower the relative humidity in the room outside of the tank.

Dehumidifiers are common household appliances for people living in moist climates.  They take a surprising amount of water out of the air and keep your environment mold-free.  By placing a dehumidifier in the room near your reptile’s tank, you are going to be able to lower the humidity in their tank as well.

Dehumidifiers can be purchased at most stores that sell home appliances and electronics.  While they can be pricy you can also find small one-room units that are relatively affordable.

4. Consider Changing Your Water Dish

The dish of water in your reptile’s enclosure is an extremely underrated source of moisture.

Have you ever stayed in a hotel with an indoor pool?  If you have, I’m sure you can imagine the humidity in the air in the pool room.  You walk in, and you are instantly sticky because of all the moisture in the air.  A lot of this has to do with the large body of water in a small enclosed room.  Your reptile enclosure might be the same way!

If you have a large dish of water in your reptile’s tank, it might be making the humidity higher than it should be.  The easiest way to fix this?  Get a smaller water dish of course!  Making sure that the water dish stays on the cooler side of your pet’s home should keep humidity levels low.  Swapping water dishes is fast and cost-effective!

Are you worried about a smaller water dish because your pet spends a lot of time in their water dish?  You have options.  If your reptile likes to sit in the water dish, there might be a reason for this and we’ve written all about it here.

5. Add Some Rice

Rice is a cure-all.  You can throw electronics in a bowl of it and they are magically cured, but why is that?

Dry uncooked rice is a natural moisture absorber.  In this form, rice has an amazing capacity to lower humidity levels.  Because of this, rice can be used as a food preservative.  But, you can even use rice to lower humidity levels in your reptile’s tank.

You probably won’t want to throw rice all over your scaly friend’s tank.  It’s not aesthetically pleasing and you never know what your pet might decide to do with it. One thing you can do with rice is to fill a sock with it and tie the top of the sock off.  You can then place the rice sock in a dark humid corner of your reptile’s tank.  This method can greatly lower humidity in small areas and can usually be started without buying any extra supplies.

A combination of the five methods mentioned above will certainly lower humidity.  But, is it possible to make your pet’s enclosure too dry?

How Can You Tell If It’s Not Humid Enough?

In your quest to lower humidity for your desert pet, you might find that your methods are working too well!  The easiest way to see if humidity levels are too low is to compare your pet’s ranges with the readings on your hygrometer.  You might also notice your pet’s skin becoming wrinkly and saggy.  If this is the case, you can scale back on some of the dehumidifying methods.  For temperate pets, you might want to check out our article on raising humidity levels here.

Final Thoughts

Lower relative humidity doesn’t have to be difficult or expensive!  However, there are many factors that affect humidity, and it’s important to be aware of all of them.  Substrate, ventilation, environment, and water features all play a huge role in the tank’s humidity.  For animals that need a dryer environment, making small changes will keep them comfy and safe.

Along with UVB, heat, fresh water, and a long list of husbandry concerns, managing humidity is just one of the many things that the careful herper has to consider!

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