The Best Turtle Substrate

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best turtle substrate

In this article, we will cover a very controversial topic, something that beginners struggle when starting out setting up their very first turtle tank.

Choosing the best turtle substrate for your shelled reptile will be important for you as a pet owner and for the turtle itself. 

First of all, it’s important for you because depending on what type of turtle substrate you will choose for your turtle tank, it will mean how much time you will spend cleaning it up and changing it.

Second, it’s also important for the turtle when choosing the substrate, since different types of substrates are more preferred by certain species of turtles.

Certain types of substrates require a different type of approach than others as some types of substrates need to be changed more often than others

Don’t have time to dive into this article? Below you can find our most preferred type of substrate for both aquatic and land turtles.

We Recommend

After testing numerous turtle substrates, we have a pretty good idea of what characteristics make the best turtle substrate, and the Zoo Med ReptiSand it’s our top choice.

  • All natural no dyes or colors added
  • Perfect for desert reptiles
  • Stimulates natural digging behavior

Understanding Turtle Substrates

A substrate is basically whatever you put on the bottom of your turtle tank or tub. 

It can be anything from sand to gravel to nothing at all. The most popular substrate that there is and that people have for their turtle tanks or tubs is gravel.

A substrate in a turtle tank can only accumulate uneaten food and wastes, which can quickly dirty the water.

Some turtle species, such as soft-shell turtles, which need a soft sand bottom, require it. However, most turtle keepers don’t use any substrate or gravel, making cleaning much easier. 

On the other hand, if a bare-bottom tank is not aesthetically pleasing to you, you are free to decorate it, but just be prepared for more frequent cleaning.

How To Pick A Turtle Tank Substrate

The substrate you choose can depend on the species of turtle that you own.

Aquatic turtles spend most of their life in the water, so you may not need a substrate as long as you provide a basking platform.

However, land turtles need substrate for thermoregulation and to give them something to dig or burrow into.

When buying a substrate, you should consider the following:

  • Safety When choosing a substrate for a softshell turtle, it should be soft enough for your turtle carapace if he wishes to burrow into it. Pebbles can be used to line the bottom of an aquatic turtle tank because your turtle will be floating above it rather than stepping on it.
  • Natural feel The goal of decorating a turtle tank is to make it look as natural as possible for the turtle, replicating the natural environment of the turtle can make him feel more at home.
  • Avoid unnatural additives Some substrates are treated with chemicals or dyes, which can be dangerous to your turtle. Make sure you check for substrates that are all-natural and wash them well before using it in your pet turtle tank.
  • Dangerous Materials Substrates like calcium sand or small gravel are to be avoided for many reasons. Either they are too small and can be eaten and cause impaction, or they can contain ingredients that can be dangerous long term for your turtle’s health.

The 5 Top-Rated Turtle Substrate

Editor’s Picks



Top Pick

Zoo Med ReptiSand, Desert Turtle White Sand Substrate


Runner Up

Carib Sea ACS00120 Crushed Coral for Aquarium, 15-Pounds


Best Budget Buy

Nature’s Ocean Aragonite Gravel for Aquarium, 10-Pound


Best Turtle Pebbles

Royal Imports Polished Gravel River Pebbles


Best Planted Turtle Aquarium Substrate

Seachem Fluorite Planted Turtle Aquaria


*Ratings are from Amazon at the time of publication and can change

The Best Turtle Substrate

1. Zoo Med ReptiSand, Desert Turtle White Sand Substrate

After testing numerous turtle substrates, we have a pretty good idea of what qualities make the best turtle substrate, and the Zoo Med ReptiSand, 10 Pounds, Desert White it’s our undeniable choice.

The look, the feel, and quality are what made us conclude that this is our top pick.

This sand’s great with any type of softshell turtle because this sand is really smooth and will make him feel right at home giving him an extra thing to do throughout the day.

There is not much else to say other than the turtle will love to burrow into this sand as this makes for an excellent heat conductor.

Combining this sand with turtle natural decorations will create a very naturalistic and attractive environment for the turtle.

Zoo Med ReptiSand Features:

  • All-natural no dyes or colors added which comes in 2 colors
  • Perfect for desert reptiles and softshell turtles
  • Stimulates natural digging behavior

2. Carib Sea Crushed Coral for Turtle Aquarium Substrate

The Carib Sea ACS00120 Crushed Coral, as opposed to sand, is great for people who are looking for a more natural aesthetic.

The weight of this crushed coral helps keep the substrate from blowing around.

Having crushed coral in your turtle aquarium will raise the ph and will stabilize itself.

Where it stabilizes will depend on the amount used and the acidity of your water during water changes.

The more you use, the higher the ph will go, up to a point.

Carib Sea ACS00120 Crushed Coral Features:

  • Contains Aragonite which originates from the ocean and includes a high level of calcium and minerals which will naturally buffer the water to a higher ph
  • Great for diamondback terrapin turtles as they like to crush hard shells with their beaks
  • Can look great in the aquarium which will give it a more natural look

3. Royal Imports 5lb Large Decorative Polished Gravel River Pebbles Rocks

One of the most popular choices when it comes to having pebbles in the turtle tank.

The Royal Imports Polished Gravel River Pebbles are big enough to prevent them from being chewed on cause impaction for the turtle.

They also have diverse variations of colors and a smooth surface to prevent injury in case they want to forage.

It can be easily cleaned and re-used by just soaking and disinfecting them in a large bucket of water for 15 minutes, rinsing until all of the visible particles are removed and the water runs clean.

Royal Imports Polished Gravel River Pebbles Features:

  • Round and big pebbles, bigger than a quarter coin size
  • Smooth and easy to clean
  • Diverse colors and different patterns

4. Carib Sea Eco-Complete Planted Turtle Aquarium Substrate

If you are looking to have a substrate that can be used to grow plants in it while at the same be a great substrate for a turtle the Carib Sea Eco-Complete is the perfect choice for this matter.

Getting to grow plants into the tank while housing a turtle at the same time will enrich the turtle’s surroundings making him feel more at home.

It all sounds too good for the turtle but you need to bear in mind that it’s pretty hard to start growing something while the turtle is there. 

He will start eating most of the plants that he will see, so it’s a good idea to have something already planted.

Even so, the turtles will love to dig into this substrate and exhaust their energy big doing so.

Carib Sea Eco-Complete Planted Black Substrate Features:

  • Encourages healthy plant root growth
  • Safe for turtles
  • Completely all-natural

5. Carib Sea Aragonite Turtle Aquarium Sand

The Carib Sea Aragonite Aquarium Sand substrate makes it an ideal aquarium substrate for North American turtle species.

It helps maintain a proper pH of 8.2 without the use of chemicals. Has incredible surface area, up to 100,000 sq inches per pound.

Most people’s tap water has a pH level of about 7.5 – 8.5. This substrate will work for most North American species, but when getting into the more exotic species, then you must pay attention to the pH levels.

With the North American species, you can get by with decreasing the pH levels to about 6.2 to assist in preventing shell diseases, but if you own a softshell turtle, we would not recommend going any lower than 6.5 for fear of hurting the turtle.

The grain size of the sand is much bigger than oolite but much smaller than pebbled gravel, it looks like a very small-grained crushed coral.

Carib Sea Aragonite Aquarium Sand Features:

  • Makes maintenance easier
  • Works great with North American turtle species
  • Proven to reduce nitrates better than regular aquarium gravel

6. Zoo Med Laboratories Aquatic River Pebbles for Aquatic Turtle Habitats

The Zoo Med Aquatic River Pebbles makes it perfect for aquatic turtle aquariums and terrariums.

It’s Great For Red-eared Sliders, Map Turtles, Painted Turtles, Musk Turtles, Cooter’s, and other species of fully aquatic turtles. 

The pebbles sizes are varied but most are pretty large, almost about gravel-sized.

Most of the rocks have blue and dark color tents, but for the most part, they make the perfect rocks for your turtle.

Zoo Med Laboratories River Pebbles Features:

  • Pre-washed pebbles
  • Safe for all aquatic turtles (NOT for softshell turtles)
  • Easy to clean/re-useable

7. Seachem Fluorite Planted Turtle Aquaria

The Seachem Fluorite substrate is a specially fracted durable porous clay gravel for the natural planted aquarium.

Its look is best suited to planted aquaria but can be used in any freshwater aquarium setting.

Flourite is most effective when used alone as a whole substrate bed, but it may be combined with other gravels.

Gravel modifiers such as laterite are not necessary.

Flourite is not chemically covered or treated and will not alter the pH of the water.

Fluorite is good for the entire life of the aquarium and doesn’t need to be replaced. Although it is pre-washed, because Flourite is a natural product, it may become dirty in transit and require rinsing before use to eliminate any residual dust.

When adding water to the turtle aquarium, fill it gradually to avoid disturbing the Flourite substrate bed.

Place a bowl in the aquarium and add water right to the bowl, allowing water to overflow softly on to the gravel bed. Initial cloudiness is typical so don’t panic when this will happen.

To remove the cloudiness, use any type of mechanical filtration.

Seachem Fluorite Features:

  • Rinse right in the bag
  • All natural Porous clay
  • For Planted Aquarium

8. Nature’s Ocean Aragonite Gravel for Aquarium

The Natures Ocean Aragonite (Grain size: 1.7 -2.5mm) it’s a premium aragonite reef substrate for aquariums that reduces nitrates and maintains the ph levels.

Makes it ideal for reef system tank bottoms, denitrifying anaerobic beds that have an extremely high surface area filter media.

This substrate is a 5-star product on all front that has great value and quality included.

The small shells and coral fragments are very porous and will hold sand. For the best results, we recommend washing this product before adding it to any tanks.

You will NEVER get all of the fine particles out, so don’t expect crystal clear water during the wash process.

Nature’s Ocean Aragonite Features:

  • 100% From The Ocean Floor
  • Increases Carbonate Hardness
  • Heat Sterilized

9. Mosser Lee ML1110 Desert Sand Soil Cover

The Mosser Lee ML1110 Desert Sand Soil it’s perfect for any type of turtle since it can be used with plants and it’s very smooth and unharmful.

This sand can be used just as well for any type of aquarium for half the price of your regular marketed turtle sand.

Mosser Lee Desert Sand Features:

  • Helps protect and retain moisture
  • 1/5 the cost of ‘official’ aquarium sand and worked just as well

10. Hoffman 14302 Western Desert Sand

The Hoffman Western it’s also a safe choice for your turtle as it’s clean and fine enough to avoid any injuries for your turtle in case hes eating it.

The sand is good for your gardening and terrarium making needs. The sand is more yellow or golden than white and it is quite fine.

Hoffman Western Features:

  • Western desert sand
  • Washed silica sand

Types Of Substrates For Turtle Tanks

There aren’t many choices for turtle substrates that are specifically made for turtles but getting to know the existing ones and why some of them are being used and preferred more by some turtle keepers is a good step in becoming a better turtle owner.

Gravel Turtle Substrate

We will go over the good and bad parts of gravel substrate. 

First off the good part is that it really looks nice and it makes it seem more natural in the turtle tank and more visually appealing. 

Another thing is that it can hold bacteria, it provides surface area for bacteria to grow on and that is going to help you with the filtration of the water. 

The bad part is that if your turtles are large enough to fit gravel in their mouths, they will try and eat it and ingest it.

The issue arises when they can’t pass the gravel, it becomes an impaction and that will block their stomachs.

And that’s why we only recommend gravel that is larger than the turtle mouth and that can’t fit it in their mouths. 

Large Rocks for Turtle Tank

We recommend using larger stones rather than small stones. Large gravel will not trap as much debris as smaller rocks will, which will help keep the water clean.

Turtles are less inclined to swallow large gravel when its large, which can cause deadly wounds.

Large, smooth stones are also less likely to harm your turtle’s carapace when he sinks in the water.

Sand Turtle Substrate

Our personal favorite substrate that we will go over is sand.

The first pro for the sand is that it’s cheap and readily available mostly everywhere. 

It also looks really nice and very natural which also helps you out to clean the turtle tank as it will not hold any waste like other substrates. 

The turtle can ingest the sand since they can pass it through with no problem.

For some species of turtle, mostly the softshell turtles, will absolutely love you if you put sand in their enclosure, since they like to burrow into it and stick their little heads up

The bad part with the sand is that if you have the layer of sand at the bottom of your aquarium to thick, over long periods of time, you can get something called anaerobic bacteria.

This bacteria can thrive without oxygen and therefore can produce nasty gases and over time can bubble out of the sand which can be toxic for your fish and turtles. 

Needless to say for that to happen, it really takes a long time to happen but it can end up happening eventually.

Bare Bottom Turtle “Substrate”

Some consider that having nothing at all in the tank to serve as a substrate is the best option.

The benefits here are that it’s really easy to keep the tank clean and there’s nothing to really hold the waste of the turtle in, nothing to clog your filter and nothing for the turtle to ingest.

Bare Bottom Substrate

The only real issue here is that it doesn’t really look great, and this is pretty much the only con that we could find with this bare bottom substrate option. 

But if you’re not bother at all by that here are some benefits that comes with having no substrate at all:

  • Easy to clean and maintain
  • Keeps the water clean for longer periods of time
  • It’s a good option if you are running low on money

Even if your turtle has the need to forage on something, there are plenty of ways to get around this such as hiding food in different decorations or giving them live foods to hunt them.

Turtle Tank Sand or Gravel

Sand is a popular substrate that many turtle keepers like to have in their tanks. Sand can be difficult to keep clean even with frequent vacuuming. Sand is perfect for turtles who like to dig in it such as softshell turtles.

If you do choose to use sand, use fine sand, like the play sand that’s being sold for children to play with.

Gravel is yet another popular type of substrate that’s being often used in turtle setups.

If you intend to place gravel into your turtle tank, be sure that’s big enough and smooth to avoid the turtle eating it.

Water Quality When Using Turtle Substrates

Some types of turtle substrates can have a more or less great effect on the water quality of the turtle tank.

Poor water conditions could mean troubles, health problems and can cause death if not identified. There are 4 aspects of water quality that are essential in maintaining water quality:

  • pH
  • Ammonia
  • Nitrites
  • Nitrates

A more acidic pH is desired because of its ability to prevent certain strains of bacteria and fungal eruptions.

The main concern for pH with turtles is that some of them depending on the species require a certain of pH setting.

Without the proper pH levels being maintained, there could be health issues that could occur for the turtle.

Commonly Asked Questions About Turtle Substrates

Q: How Often Should I Change The Substrate?

It depends on the substrate that you use. If you use gravel these can be cleaned and reused again. If you are using sand it’s a good practice to change it every few months. If it’s a planted substrate you don’t need to replace this at all. 

Q: Can I Put Rocks In My Turtle Tank?

Yes. As long as they don’t present any sharp and cutting edges, it’s safe for them.

Q: What Is The Best Thing To Put In The Bottom Of A Turtle Tank?

The best thing to put at the bottom will depend on the type of species your turtle is. Most will argue that having a bare bottom tank meaning nothing at all, is the best choice.

Q: Is Sand A Good Substrate For Turtles?

Yes. Especially for the softshell turtles since they like to burrow into it. It’s also a much safer option than small gravel since the turtle can pass it when ingested.

Q: Do Turtles Need Humidity?

Aquatic turtles having low humidity is not an issue since they live in water. However, having a high humidity can be concerning while he’s basking because it will prevent the shell to dry off completely.

Q: Will Turtles Eat Substrate?

There is no real scientific research to support this theory so our evidence is anecdotal. From what we’ve seen turtles will try and eat almost anything that can fit into their mouths, so that’s why our list is comprised of substrates that are safe for the turtle even if they eat them.


Choose bedding that fits your turtle’s needs closely and look for safeness as the number one rule when choosing a substrate. 

Also try to stick to substrates from the very best brands to avoid any complications.

Use a combination of different types of substrates that could fit your turtle type of species.

Remember that the best turtle substrate differs from turtle to turtle, and it may be a matter of trial and error until you find something that fits their needs.