Pros and Cons Of A Bare Bottom Fish Tank and How They Work

A bare-bottom fish tank, also known as a “bare tank,” is a type of aquarium setup where the tank floor is left without any substrate or decorations. This setup has pros and cons, and it’s essential to understand how it works before deciding if it’s the right choice for your fish.


Easy to clean:

Without any substrate or decorations, it’s much easier to clean the bottom of the tank. This means less time spent scrubbing and more time enjoying your fish. When the substrate gets too dirty, it can be easily cleaned off with a sponge or garden hose.


A bare bottom tank offers more oxygen to the water, which helps keep the water cleaner for longer. This also means less need for live or fake plants, as the plants eat up oxygen in your tank.

Better water quality:

Without a substrate, there’s less chance for debris and waste to build up, which can lead to better water quality. This is especially important for tanks with sensitive fish or invertebrates. This means more oxygen and reduced stress, both of which are good for the health of your fish.

Many aquarists choose to leave their tanks bare-bottomed as it offers benefits that other setups do not, but there are also many disadvantages.

Most fish tanks will have a substrate (usually sand or gravel), decorations (plants or rocks), and water level markings. A bare bottom tank does not have these, so it’s only suitable for some types of fish or species. These tanks should be used only with fish that can adapt to the loss of such amenities.

Better visibility:

With no decorations or substrate, it’s much easier to see your fish and keep an eye on their health. Here’s an example:

You can see when the gravel gets dirty with a bare bottom tank, and it’s easier to clean than a substrate-riddled tank. However, the lack of decorations and objects can make it harder to set up your tank correctly (more on this in the “Setup” section), and any sudden changes in water chemistry can be difficult to clean up. This is especially important if you’re using submersible lighting.


Setting up a bare-bottom tank is often less expensive than buying substrate and decorations. This is because you already have the tank and its frame, which is much cheaper than buying a new tank, even if it’s slightly larger than the old one. It is also more affordable to purchase bare bottom tanks from online stores (such as Aquahobby). These bare-bottom tanks are usually sold for about half of what full-tank setup costs.

Better fish compatibility:

Most fish do particularly well in bare bottom tanks, especially when they’re young and small. This is because fish such as catfish or loaches can burrow into the substrate if they need to retreat to hide or if their habitat gets too dirty.


Limited options for fish:

Some fish, such as cichlids and other bottom dwellers, need a substrate to feel secure and comfortable. These fish will not do well in a bare bottom tank. This is because these fish need places to hide if they feel threatened or if the tank gets too dirty.

No hiding spaces:

Bare bottom tanks don’t offer any hiding places for fish. This means their home has less security, and it’s less fun for them to live in. It also means fewer plant options, which will be covered in the next section.

No natural look:

With a substrate or decorations, a bare bottom tank can look plain and interesting. Bare-bottom fish tanks have been described as “sparkling floor aquariums.” This is because no decorations make the tank more natural or attractive. The lack of a substrate or decorations can make it harder to make your tank look natural, but there are still things you can do. You can use rocks or plants at the bottom of the tank to help give a sense of depth, and there are many decorations you can use to add a natural look.

Not all fish will work without a substrate or decorations. You should add decorations if you want your fish to feel more at home so that they will stay healthy and happy. That said, if your fish has specific needs that aren’t being met in the tank, it’s best not to keep them in the tank, no matter how well it’s decorated.

No hiding spots:

Fish need places to hide and feel secure, and a bare bottom tank offers no hiding spots. Here’s an example of what this can look like:

No beneficial bacteria: Substrates can provide a home for beneficial bacteria that help to keep the tank’s water clean and healthy. Without a substrate, these bacteria will not be present in a bare bottom tank.

How it works:

A bare bottom tank is set up much like any other tank but without a substrate. The tank should be filled with water, and a filtration system should be installed. It’s essential to use a high-quality filter that can handle the size of the tank and the number of fish in it.

It’s also essential to properly cycle the tank before adding any fish. Cycling a tank means allowing beneficial bacteria to grow and establish themselves. Without these bacteria, the tank’s water will not be able to support fish.

Once the tank is set up and cycled, it’s time to add fish. As mentioned earlier, it’s important to choose fish that are compatible with a bare-bottom tank. Fish that need a substrate, such as cichlids, should not be kept in a bare bottom tank. Bare bottom tanks are best used only with fish such as catfish or other bottom-dwelling fish.

When cleaning a bare bottom tank, it’s essential to make sure any waste doesn’t fall into the gravel or decorations, as this can seep into the water and harm your fish. Filters should be cleaned regularly, and the tank should be cleaned periodically. Fish food should also be removed from the tank, so it does not rot in your aquarium.

Properly cycling a new tank ensures that your fish won’t develop disease or die because of poor water quality.

It’s also important to remember that a bare bottom tank will require more frequent water changes than a tank with a substrate. This is because, without a substrate, there’s less chance for debris and waste to build up, which can lead to better water quality.

In conclusion, a bare bottom fish tank has its pros and cons. It’s easy to clean, provides better water quality, and offers better visibility. However, it also has limited options for fish, no natural look, no hiding spots, and no beneficial bacteria. With proper maintenance, a bare bottom tank can be an excellent option for fish-keeping enthusiasts. Before setting up a bare bottom tank, weighing the pros and cons and choosing fish compatible with this type of setup is essential.