Types Of Aquarium Substrate

Setting up a home aquarium requires many components for fish to live in. One of the components, which is also essential is the substrates. A substrate is just a fancy term to refer to something that is beneath something. There are many different types of aquarium substrate available to choose from.

Types Of Aquarium Substrates

When it comes to the types of substrates for aquarium, there are many different choices to choose from. Substrates include gravel, dirt, marbles, sand, and even artificial substrate.

An artificial substrate is an imitation gravel that has the natural look and colors of the real one. Some fish keepers prefer artificial substrate because of their large varieties of colors and shapes you can get.

With natural substrates, there are limited colors and shapes to choose from due to them being natural. However, natural substrates are much better than artificial substrates because you can add fertilizers to them. This improves the growth of the plants

Aquarium Gravel

Aquarium gravel is the most popular substrates used in an aquarium. Gravel comes in many different colors and sizes. They are a perfect choice especially when doing aquascaping.

The gravel found at most pet stores or online stores will be chosen specifically for aquarium use. There are some types of gravel that are not recommended for use in the aquarium due to their size and properties. In addition, this gravel is cleaned and free of any parasites or pests which is usually found in their natural habitat.

Besides the stores, you can actually find gravel in the outdoors as well.  Nearby streams and rivers, lakes, and even the ocean have gravel you can use in the aquarium.  If you’re planning to use the gravel from this area, make sure to clean it well first.  Cleaning will remove parasites and pests that might be in the gravel.   You can easily clean the gravel by placing them in a large bucket and use a chemical such as Seachem ParaGuard which can be found on Amazon.  This chemical will kill all parasites and pests in the gravel before placing them in the aquarium.  Leave the gravel in the bucket with the chemical solution for a couple of hours and your gravel should be pest-free.

Aquarium Sand

Sand is the second most popular substrates to use in an aquarium. Aquarium sand actually will help create a pleasing-looking aquarium due to its texture and color. In addition, sand makes a great substrate to use for those who aquascape their aquarium.

Most species of fish, especially saltwater fish use sand to lay their eggs in. Sand is the perfect material to hide their eggs and keep it protected until it hatch. If you’re planning to breed fish, sand is an excellent choice to use as a substrate.

Other creatures besides fish will benefit from having sand in the aquarium.  One creature, the shrimp prefer sand substrate as they are used to it in the natural habitat.  They will use sand to bury themselves to hide from predators.  For breeding shrimps, the sand is the perfect place to lay their eggs in.

However, with sand, there are some disadvantages to using them. Since they are small in size, they tend to cause damage to aquarium filters. Sand is also hard to keep live and artificial plants stationed, especially if there are a lot of large fish in the aquarium.

Aquarium Soil

Growing live plants in the aquarium will require aquarium soil. This substrate soil provides nutrients for the plants to grow. Aquarium soil bought from the pet store will be formulated with other materials to prevent it from mixing with water. Doing so will prevent the water from being dirty and muddy due to the soil.

Some aquarium owner prefers not to use aquarium soil for other reasons. It could be due to the species of fish they have or the aquascape in the aquarium.  If so, live plants still can be grown without aquarium soil.  You will just need to use a different substrate and add root tabs underneath the substrates as a food source for the plants.

A word of caution, the soil used for an aquarium is not the same soil you use in a garden.  The soil used for gardening has different textures and properties so it will not work if you use them in an aquarium.  If you do, you’ll find yourself with a big mess and will need to drain the entire aquarium out.  In addition, you’ll need to clean all the plants and decorations as well.   So remember to use only aquarium soil which has been formulated so it will not mix with water and create a mess.

Coral Sand

Another type of aquarium substrate is coral sand.  Coral sand or coral gravel is made of calcium carbonate. This material tends to slowly dissolve into the water. This actually helps by counterbalancing acid build up in the aquarium. If you have a lot of fish, your aquarium will end up with a lot of fish waste and uneaten food. All those waste will release toxins such as ammonia and acid. Coral sand will naturally help prevent the build-up of toxins to a dangerous level. However, you shouldn’t depend on coral sand to eliminate the toxins from the water.

Since coral sand is not widely popular to use but want the benefits of it, some fishkeepers will mix coral sand with other substrates.  Coral sand will blend in well with aquarium sand and gravel.


Another great choice for the substrate is marbles. These substrates are usually flat and come in a variety of colors. Marbles are great to use if you’re planning to do aquascaping or making your aquarium stand out from the crowd.

There are many different types of marble in the market.  Some are round and are used for decoration purposes only.  These types of marbles may be a health hazard for the fish since they might be able to swallow it.  To be safe, make sure to use only marbles that are made to be used for aquarium only.

Marbles tend to not be used by a lot of aquarium owners due to their gap size. Marbles have large gaps between them and can cause some problems. Food and other debris can fall between the gaps and get trapped. In addition, it makes the beneficial bacteria harder to breakdown fish waste.

If you’re looking to do aqauscaping with marbles, you have a lot of choices and designs to choose from.  Marbles can be used to create a unique environment for the fish.  Not only will you benefit from the appearance of the aquarium, so will the fish.

Why is Substrate Important In An Aquarium?

Substrate not only makes the appearance of the aquarium more appealing, but it also provides many other benefits as well. Below are some of the importance of having a substrate in an aquarium.

Natural Habitat

By having a substrate in the aquarium, you’re providing something that is found in their natural habitat. In the wild, whether it be a pond, lake, or ocean, there’s something beneath them. By having a substrate in the aquarium, you’re giving the fish an environment like their natural habitat.


Without a substrate, the aquarium will look empty and boring. By adding substrates, it enriches the look of the aquarium and makes it worth looking at.

For Plants

Whether you have live plants or artificial plants, substrates are needed to help keep them grounded.

For live plants, they need substrates to help them grow.  The roots of the plants take in nutrition from the aquarium substrates such as the aquarium soil.

On the other hand, artificial plants require substrates to keep them from floating around. Artificial plants are made of plastic materials. For that reason, they are lighter than water which will cause them to float to the top if it’s not grounded.  The substrates will be added to the base of the artificial plants to keep them in place.

Nitrifying Bacteria

Beneficial bacteria are vital to the health of an aquarium. They provide filtration of natural biological cycling processes such as breaking down waste from the fish. A substrate provides these bacteria in a place to do their job.

Fish Eggs

Most species of fish lay their eggs in some type of substrates. Substrates provide protection for the eggs until they hatch.

Do you need Aquarium Substrates?

The simple answer is no you don’t need a substrate in your aquarium. However, most species of fish will require substrates because that’s what is natural to them. Fish uses substrates to hide their eggs, scavenges for food, and for protection.

If you must and don’t want to use any type of substrate for the aquarium, choose the correct species of fish that will be able to live in it.  A fish that require a substrate to live and if there are none, they will become stressed.  When the fish become stressed, it can lead to illness and even death.


As you can see, there are many different types of aquarium substrate you can use in the aquarium tank. Choosing the right substrate for your aquarium will depend on your personal preferences and how you want the aquarium to look.  Make sure to not overlook the maintenance side of using the substrate.  You’ll need to clean out the waste from the fish and uneaten food every month.  This will ensure not just the substrate will be clean, but the fish will be healthy as well.

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