Lava Rock for Aquarium (The Hidden Benefits and Dangers)

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Adding the right aquarium landscape can not only enhance its aesthetics but also provide a better environment for your fish. 

While there are several landscaping options to choose from, lava rocks are one of the most commonly used. Moreover, there are various types of lava rock for aquarium to choose from, giving you the space to personalize the look of your home aquarium. 

Follow this guide to know more about the benefits and uses of adding lava rocks to your aquarium. 

Is Lava Rock Safe for Aquariums

Long story short, lava rocks are entirely safe and highly beneficial for aquariums. These rocks not only provide ornamental beauty but also help denitrify bacteria. In turn, this helps create a better environment for fish to thrive in. 

It is essential to know the process of how lava rocks help denitrify bacteria. As such, the fish waste contains high ammonia levels which can be highly toxic. However, denitrifying bacteria can help combine oxygen and ammonia to create nitrite. 

Now, keep in mind that nitrite is still toxic for an aquarium, but it is less harmful than ammonia. The addition of lava rocks helps facilitate this vital process, improving the water quality of the aquarium and creating a healthy environment for your fish. 

Lava Rock Benefits for Aquarium

Lava Rock for Aquarium Benefits
Photo: vergetalks

There are multiple benefits of adding lava rock to your fish tank. Let us discuss some of them in detail below. 

Remove Nitrates

We already talked about how lava rocks can help remove ammonia from fish tanks by converting it to nitrite. However, most fish tanks also contain certain levels of nitrate in them. The higher the concentration of nitrate, the more dangerous it is for your fish. 

Fortunately, adding the right amount of black lava rock or red lava rock can help remove nitrates from the tank.

Harbors Beneficial Bacteria

We all know that bacteria can be harmful to humans, fish, as well as plants. However, not many people are aware of the fact that good bacteria exist. This kind of bacteria is highly beneficial for fish and your aquarium environment. 

Moreover, adding lava rocks to the fish tank essentially enables the conversion of ammonia and oxygen that is already present in the fish tank into denitrifying bacteria. This bacteria helps improve and purify the water quality in fish tanks, thereby creating a healthy environment for fish. 

Aesthetic Beauty

Most tank owners know how great it feels to add all kinds of ornaments to their fish tanks at home. These decorations add aesthetic beauty to the tank and make it a better living environment for your fish and plants. 

One of the best ornaments that you can add to fish tanks is lava rocks. The best part is that these rocks are available in a variety of colors and shapes, adding natural texture, depth, and color to the tank. 

Furthermore, these rocks emulate the natural habitat of fish, helping them cope better and thrive in tanks at home. Also, the addition of this natural landscape inevitably adds beauty to an otherwise drab-looking tank.

Build Caves & Hiding Places

If you observe a fish tank carefully, you may notice that certain species of fish or invertebrates are typically timid or anxious. However, in their natural habitat, these fish species find common shelter spaces like rocks, caves, or shells. 

Since lava rocks are natural rocks that look similar to their living environment in the wild, many fish species like to use them as hiding places. These fish species feel comforted and calm when they are provided with caves and shelter spots. Moreover, these spots often act as closed spaces for certain fish species to mate or spawn. 

Break Up the Sight Lines

Breaking up the line of sight between different species of fish may initially sound unnecessary. However, once you own certain fish species that can be territorial and aggressive, the need for creating a hardscape that breaks the line of sight will become apparent. 

As such, lava rocks can form excellent barriers and hiding spots for these fish species. They can use the rocks to seek shelter from other aggressive fish species and mark their territories. 

Furthermore, lava rocks can also help break the line of sight between two aggressive fish species, ensuring that there are fewer visual triggers between them to initiate aggression. 

The Hidden Dangers of Lava Rock in the Aquarium

Now that we have discussed the various benefits of placing lava rock in an aquarium, it is time to discuss the other aspect. Of course, there are a couple of hidden dangers of having lava rock in your aquarium. More often than not, you can take certain measures to reduce the potential risks it may have. 

But first, let us discuss some of the hidden dangers of putting lava rock in the aquarium. 

Scratch Your Fish

You may come across a variety of shapes, colors, sizes, and textures of lava rocks on the market. Sure, some of the lava rocks that have pointy edges and stand out in an aquarium look more striking than other ones. However, lava rocks with pointed edges are risky, as they might scratch your fish, especially the smaller ones. 

Of course, you can try to place them strategically to avoid scratching. That being said, we recommend opting for lava rocks that have rounded edges, as this is a safer option for your fish. 

The size of the lava rocks does not matter as much as their shape. So, keep an eye on the shape of the lava rocks you wish to put in a fish tank. As we’ve already mentioned, try to opt for the ones that have rounded edges to protect your fish. 

Waste And Debris Accumulates

Another obvious disadvantage of having lava rocks in a fish tank is that they facilitate the accumulation of waste and debris. As you may imagine, it is much easier to regularly clean a fish tank that has an undulating bottom. However, the addition of lava rocks can make it slightly challenging to clean the tank properly. 

In order to clean a fish tank with lava rocks, you will need to remove them, clean thoroughly with a cleaning solution and a brush, and place them back. This process might seem arduous to some tank owners, so they often shy away from placing lava rocks. 

As an alternative, you can opt to place an aquarium filter in your fish tank. Although placing a filter media does not mean that you will never need to clean the fish tank, it helps trap some of the dirt and debris and filter the water. Thus, it may create a healthier, cleaner environment for your fish. 

What Type of Aquarium Are Lava Rocks Good For?

Shrimp Tank

Due to the porosity of lava rocks, it is one of the best and safest hardscapes that you can add to a shrimp tank. Furthermore, these rocks help create natural feeding grounds for baby and adult shrimp. It does not naturally raise TDS in the tank and acts as a firm base for placing plants in the tank.

Cichlid Tank

Photo: chriscichlids

Lava rocks are excellent for Cichlid tanks as they help denitrify bacteria and provide suitable hiding spots for the fish species. Furthermore, they create a natural habitat and are excellent spaces for breeding. 

How To Prepare Lava Rock for Aquarium

Wondering how to prepare lava rock for your aquarium? Take a look at these simple steps.

Clean the Lava Rock 

It isn’t a good idea to purchase lava rocks or dragon stones from a store and immediately place them into a fish tank. Begin by taking a bucket of dechlorinated water and brush and scrubbing the rocks to clean them thoroughly. Ensure that the water runs clear before taking them out of the bucket. 

Cushion the Rocks

Add a styrofoam sheet or some cushioned mats designed for aquariums at the bottom of the tank. This ensures that the lava rocks are not uneven and do not have any hard pressure points. 

Add Substrate 

Next, add some sand or crushed coral to the bottom of the tank. You can even use silicone to glue the sharp edges of the lava rock so they do not damage the glass or hurt the fish. 

Add The Lava Rock

Finally, add the lava rock into the tank, but ensure that it is stable. Otherwise, one side may tip over and crack or break the aquarium glass.

Final Thoughts 

That’s all you need to know about lava rock for aquariums. 

Ensure that you purchase the lava rock from a reputable store. You can even choose to browse online stores to find the most suitable type of lava rock for your home aquarium. 

These rocks are highly beneficial for most tanks and create a healthy, happy, and colorful environment for fish. 

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Jeff Colt

Jeff Colt

Hello, I'm Jeff- an aquarium enthusiast with over 25 years of experience caring for a wide array of tropical fish, including koi, goldfish bettas, cichlids and more! For me: Aquariums are like jello - there's always room for more!

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