[Definitive Guide] How to Clean Fish Tank Rocks (With & Without a Vacuum)

How to Clean Fish Tank Rocks

How to Clean Fish Tank Rocks: Regular cleaning is crucial when it comes to maintaining an aquarium. It would be best if you even cleaned the rocks in your aquariums, as they can be covered with algae and debris. Algae cover the surface of the aquarium when the water is not completely clean, or something in the dimension of the tank or maintenance is irregular. Eventually, the dirt will be turned into microbial contamination, causing severe damage to the fish and degrading the water quality.

Some general steps to prepare rocks for an aquarium

Rocks are known to harbor various contaminants, including viruses, bacteria, parasites, and pollutants. The hardest part of building tanks is figuring out which rock type is best for the setup you have. The objective is to find neutral rocks so that they do not cause sudden changes in water parameters. An increase in water hardness or a drastic fluctuation in your pH level can cause a significant imbalance in your tank, causing negative reflections on your pet fish. Increased stress levels in fish will likely make them ill. Many types of rocks are safe for fish and aquarium invertebrates. When assembling your hardscape, select the suitable stone for your type of aquarium and sanitize them correctly, rinsing well under running water and sterilizing it under the sun or in the oven until it is completely dry, thus getting rid of possible aquatic pathogens.

Cleaning decorations and rocks

Clean the inside of the glass to remove debris and other materials, such as signs of algae; if the surface is dirty, it should be cleaned. Never use soap or other products, it can be challenging to remove the soap, and the same traces can harm your entire aquatic system. Rocks and driftwoods are bleached to remove algae from them. However, plant roots do not tolerate bleaching. To bleach live plants, add a 5 percent bleach solution to a room with the plants, and a 2-3 minute bath, then rinse thoroughly before placing the plants in the aquarium. Do not place them in the aquarium until there are no more chlorine odors.

How to Clean Fish Tank Rocks

Safe rocks to prepare for freshwater aquariums

The rocky soil is colonized by bacteria that benefit the health of the aquarium, mainly those responsible for biological filtration. Rocks were created by nature containing infinite grains of minerals and a certain amount of porosity. Although the stone is considered safe for use in an aquarium, there may be minerals that would make it potentially dangerous for the aquarium’s life. You can find some fascinating textured freshwater rocks online.

How often should you Clean Fish Tank Rocks?

Gravel can quickly cause an explosion of pollutants when the tank is overcrowded with waste if you overfeed your pet. If you have a densely planted tank, you can stop vacuuming gravel once a week but do so at least once a month. Try changing your water weekly. Decaying plant leaves in the gravel are not at risk, so dead plants and decay are not causing problems. Gravel is necessary even if you don’t have enough fish – and some species cause a lot of waste – like goldfish and Oscars.

Cleaning fish tank rocks

You must carefully clean even the smoothest rock before sterilization. Any porous or damaged rock or rock requires extra cleaning. Soap cannot be used in this situation. Soap residues are difficult to remove and can also be dangerous to aquarium fish. The next stage in the rock preparation process is to get rid of bacteria or microorganisms deposited on the rocks.

Safe rocks to prepare for saltwater aquariums

Live rock or dry rock is made up of coral fragments that emerge from the underwater coral reef. This type of rock is usually collected in deep water. They are called live rocks because they create excellent habitats for beneficial bacteria, invertebrates, and lots of marine life.

Why it’s essential to clean fish aquarium rocks.

Fish food scraps, fecal matter, and decaying plant matter can become trapped in your aquarium’s gravel substrate. Leaving this debris exposed is known to create a hostile condition in fish that can endanger and kill them. Because of this, you must carry out the correct cleaning periodically.

Where can I find rocks for my aquarium?

To get rocks safe for aquarium, you want to know where they came from. Ask the seller for all information about the stone, the place of origin, if it is of limestone origin, if anything changes in the chemistry of the water, etc. If you choose to collect, use common sense and always sanitize correctly before placing them in the aquarium.

How should I clean my rocks?

For preparation rocks, for aquarium, you must use fish-free vacuumers and a little time. The task of cleaning and sterilizing the stones is impossible to avoid. A fish-safe water cleaner and time wasted will be needed if you’re preparing the aquarium.

How to Clean Fish Tank Rocks

Rocks You Shouldn’t Put In An Aquarium.

Some rocks can potentially leak toxic chemicals into your aquarium or negatively affect the water’s biochemical balance.


Calcium carbonate released by the mineral calcite can increase water hardness. In some situations, it also causes water to change pH. More resistant fish with more challenging water may never be affected by the addition of calcite. But for more sensitive fish in softer, acidic waters, it can kill sensitive fish. It’s not worth adding calcite rocks to your aquarium as – calcite rocks tend to decompose slowly over time.

Rocks that were kept in other treated tanks

Rocks in an aquarium where the medicine was used to treat fish should not be reused in other tanks. Porous rocks could retain some chemicals for a very long time and are easily absorbed by the new aquarium.

Rocks from contaminated waters

You can clean and sterilize stones to some degree, But fish-safe disinfectants won’t remove traces of dangerous contaminants. It is safe not to have any salt or debris collected in the wild in an aquarium.

Rocks that crumble easily

Sedimentary rock is the one that will generally crumble when submerged for long periods. Even if the rocks look fantastic when you collect them, they should always crumble apart in your aquarium.

Sharp-edged rocks

Stones have rough edges and can cause fish damage in your tank. Avoid adding such types of rocks to fish tanks or fish that have long flowing fins.

Rock with visible specks of metal or rust

Metal deposits embedded in stone can become impractical. Don’t put stones with visible tin in them; it’s a vast hazard too.

How do I test rocks for fish tank safety?

Before adding the chosen rock, you can test it to see if it could be harmful to your tank. The limestone and granite remnants are a ruined disaster that is about to happen.

Test carbonate content

One way to check calcium carbonate content on rock is to splash with vinegar. Unless the stone is calcite, the reaction can quickly become apparent. Don’t worry about washing the rocks and their sterilization because they are safe for marine use. The rock surface will be swollen through an enzyme reaction between vinegar and calcium.

Crumble test

A crumble test is also essential to keep the rock you collected out of your aquarium from deteriorating. Fill a container with old tanks of water and soak the stones for 24 hours. If they remain unspoiled after the soak, they should always be safely kept in an aquarium.

Test porosity

If you add rocks to your tank to give nitrifying bacteria a chance to grow in volume and spread, you should choose rocks with greater porosity. In visual terms, porous stones are darker in rough areas and dry faster than smooth rocks when wet.

Test water parameters

The only way to know if something is going to affect fish is to test the water that comes out of the tap with the water in contact with the rocks and compare the result.

Cleaning the inside glass

A wide range of aquarium glass cleaning products is available on the market, from long-handled scrapers to magnetic scrapers. Buy algae remover pads at pet stores. Pay attention to edges and places that may be scratched or brittle.

Outside glass and fixtures

Regular glass cleaners products contain ammonia toxic to fish. Standard lime cleaners are much more toxic. It is highly recommended to use vinegar or a safe aquarium cleaner. Always wipe away the surface with a clean damp cloth. Wipe the dust and the dirty from light and glass.

Siphon to clean aquarium gravel

There is a lot of accumulation of dirt and bacteria; to clean it correctly, we must aspire to it with the aid of a siphon. The water collected with the dirt is discarded, replaced by freshwater, without chlorine, and with the same physical and chemical standards as the water in the aquarium. A water change of around 30% weekly will bring numerous benefits to your tank. Remember to unplug the heater and other equipment before changing the water, thus avoiding failures and malfunctions. Do a thorough vacuum job over the entire substrate, paying particular attention to the dirtiest areas. Replacement water has the same temperature as the aquarium water, ensuring it is the same as the replacement water you will use during the change.

Do you have to wash aquarium gravel?

The least you should do is remove food and dirt from the substrate. Failing to clean the gravel can make the water slower and dirty, requiring more frequent cleaning. Algae thrive in muddy gravel, accompanied by a rotten egg odor from pockets free of excess oxygen around the compact stone. Therefore, clean the rock to remove dirt and break up the small holes in the packed gravel. Alternatively, aerated calculations can help reduce water movement. Use a stone in the air to improve the flow of water in the tank.

Healthy and happy community aquariums require clean, safe environments.

If you suddenly remove rocks, driftwood, and substrate from your tanks, you risk losing valuable colonies that neutralize animal waste. Remove hardscape and substrate only in case of disabling or modifying the entire aquarium. The correct way to proceed with the cleaning is not to remove anything, not even the fish. The windows will be cleaned with the help of a special cleaner, the substrate using a siphon, and rocks and other objects manually.

The Best Aquarium Rock Buyers Guide – 2023 – Aquarium Hunter

If you are setting up your tank for the first time, you may want to consider adding some rocks to your tank. While you may think of stones that simply serve as a visual aid in your tank, in fact, they have many benefits for your fish and other things that live in your tank.

Best Aquarium rocks serve many different purposes. They help create a natural-looking aquatic landscape, provide a home for colonies of beneficial bacteria…

Comparison Table

CustomSiteStripe ImageTitleReviewBuy
Top PerformanceNature’S Ocean Coral Base Rocks For Aquarium4.5/5.0Check Price
cheapestCarib Sea ACS00372 3 Case South Sea Base Rock Bag For Aquarium4.6/5.0Check Price

Give your fish and others a place to explore, and it can even provide a base for coral to grow.

What are the best aquarium stones? It depends on what you are looking for!

Today’s post covers it all. I will review the types of stones used for freshwater aquariums and then compile a list of the best stones to buy online. In the posts, there will be affiliate links where I can get a commission if you decide to make a purchase at no cost to you. Let’s get on with that revelation.

The 9 Best Rocks For Freshwater, Saltwater Marine Aquariums

Best Aquarium Rock Reviews

1. Carib Sea ACS00370 South Sea Base Rock for Aquarium


 Best Aquarium Rock

This base rock of the southern seas of the Caribbean Sea is absolutely beautiful. They are formed by natural weather processes and erosion that create beautiful shapes that make any aquarium look like the bottom of the ocean. However, these rocks do more than just look cool.
They have an impressive 50% empty space for incredible porosity levels. While water moves easily through this rock, it is also extremely durable and long-lasting. Plus, all the little nooks and crannies are the perfect place for beneficial bacteria to thrive.
The rock of the South Seas has more structure than almost any other rock used for water construction. It is safe for all saltwater tanks and freshwater systems operating at a high pH. This rock is composed of calcium carbonate that supports a high pH and is mined from ancient underground coral reefs. You can use it as an alternative to live rock or as a base to start a colony.

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2. Nature’s Ocean Coral Base Rocks for Aquarium

 Best Aquarium Rock

These Nature’s Ocean Coral Base Rocks come in 2 large pieces, each about 12 to 18 inches, for a total of about 40 pounds. To get the shape you want, just use a hammer and chisel to cut it through until you have what you need.

You’ll find that if you’re working with large chunks of rock, dust and other debris will break away to open them up further, revealing holes and tunnels that you may not have noticed right out of the box.

This is an all natural 100% premium aragonite stone. They are absolutely covered in holes and cracks, which makes them exceptionally porous. It also allows you to create very elaborate and interesting setups as you lay a foundation for new coral growth. It is also a great addition to established coral tanks.

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3. Carib Sea ACS00372 3 case South Sea Base Rock Bag for Aquarium

 Best Aquarium Rock

This next rock from the Caribbean Sea is a base rock in the South Seas that’s perfect for reef and marine tanks or if you’re looking for something to add with African cichlids. It is an excellent base for living coral because it is clean and extremely porous with macro and micro parasites.

There is no need to cure this stone, it is immediately ready to go in your aquarium. This pack contains a total of 10 pounds, but as each stone is unique, the number of pieces in each pack varies.

One great thing about this rock is that it is filled with so many nooks and crannies that building a structure to suit a waterscape is quite easy.

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4. Marina Naturals Rock Outcrop

 Best Aquarium Rock

For a piece that really makes a statement, this Marine Naturals unlock is sure to turn heads.

These large, intricately designed formations can be used individually or together with others to create arches, cavities and tunnels that fish will love as it gives them plenty of nooks and crannies to swim and hide.

This product is made of non-toxic material that does not affect the chemistry of the water. It is safe for freshwater and saltwater aquariums.

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5. Deep Blue DecoConcepts Texas Holey Rock

 Best Aquarium Rock

Last on our list is Deep Blue’s man-made Texas holey rock. Although it is not a natural rock, no one will be able to see it because they look very realistic. If it is in an aquarium, it is indistinguishable from the real thing.

Deep Blue uses polyresin material that is safe for any aquatic environment and does not alter the chemistry of the water. It is safe for plants and animals.

This design is very long and hollow and the fish love it. They are attracted to it because it makes their environment more interesting. Add interesting arches and holes for them to swim in and create a focal point in the aquatic landscape.

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6. Ohko Dragon Stone Rock – Great Rocks for Planted Tanks

 Best Aquarium Rock

Ohko Dragon Stone is one of the favorite aquarium stones to use in Iwagumi Aquascapes. These rocks are not only beautiful, they are also natural in nature. They will not change their pH or hardness because they are based on granite. They look great in any planted tank setup. They are full of holes, nooks and crannies, making them great rocks as a natural refuge for your fish.
These are the hot stones for pro aquascaping projects these days. Watch the video above from BucePlant to see how amazing they look. Like any favorite aquascaper rock, they come at a higher price.

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7. Black Mountain Seiryu Stone – Best Value In Unique Looking Rocks

 Best Aquarium Rock

If you are looking for a unique looking Best aquarium rock, check out Black Mountain Seiryu Stone. The unique white veins really show up in a waterscape. They won’t change your pH or hardness, so you can add them to any aquarium setup. These rocks are hard to find, so be wary if you like them and want to buy one. The best thing about buying from our link is that Buce Black Seiryu sells very high quality and in packs up to £30!

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8. Black Lava Rock – A Great Budget Aquascaping Rock

 Best Aquarium Rock

Quality lava rock is hard to find online. It is quite common to see lists of lava rocks used as biomes or chimneys. This makes sense because they are excellent at harboring beneficial bacteria and are excellent hearthstones. However, this limits what you can buy online. When it comes to aquarium lava rock, these black lava rocks from BucePlant are exactly what we’re looking for. These are large stones with unique shapes, unlike what you will find in most pet stores. If you are looking for quality lava rock, check out their store and selection.

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9. Traditional Seiryu Rock – The Aquascaper’s Choice

 Best Aquarium Rock

If you want a professional quality waterscape rock, but the Ohko is out of your budget, I highly recommend Dive Seiryu Rock. Seiryu is the godfather of all water rocks. These are stones collected by hand at Buce. With their excellent customer service and high-quality reviews, you can’t go wrong!

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Types of Rocks to Use For Aquarium

There are different types of natural stones that you can put in an aquarium. They are classified into 3 categories: sedimentary, igneous and metamorphic.

Sedimentary rocks include limestone, sandstone, and shale. They are made of small particles and chunks of sediment that settle over time and press against each other. As time goes by, the cycles repeat. This forms layers that are actually visible in most sedimentary rock formations.

Igneous rock forms when molten rock crystallizes from the Earth’s core or reaches the surface. Finally, metamorphic rock is the result of another type of rock being subjected to intense heat and pressure causing it to change from one shape to another.

Be sure to do your research before adding rocks to your aquarium that are not from a reputable company. There are some that you should definitely avoid such as limestone, marble, geodes, dolomite and shells or broken corals in tanks, except those in which African cichlids live.

Also keep in mind that not all aquarium stones you buy are natural stones. Today, there are companies that make polyresin bricks that look just as real as those found in nature. They’re usually a bit cheaper than the real thing, but because they’re made from molds, they don’t offer that much variety.


How to Choose Rocks for Aquarium?

There are a few important things to keep in mind when choosing rocks for your aquarium.

First, you should know that the rock is suitable for aquariums. If you order from a reputable company, you are almost guaranteed to receive a safe aquarium product. While it may be tempting, it’s not a good idea to collect rocks outside and assume it’s safe to put them in a tank.

Avoid stones with sharp edges. Some of the natural rocks we include in our list may break during shipping or you can choose to modify their shape and size. If so, round off any sharp edges.

If you are using real rocks that are not hollow or porous, be careful not to exceed the weight limit for your aquarium as this can cause significant damage. Also make sure there is a layer of sand or pebbles between the rocks and the glass bottom of the tank.

Soak or clean the rocks before adding them to your aquarium. Some stones need to be cured by boiling them in water. Follow the instructions that came with your Best aquarium rocks to be safe.




Generally, using rocks you find outside in your aquarium is advised against. This is because the rocks outside have not been treated and can therefore sometimes contain micorogranisms that could harm your fish. They can also contain calcium which can alter the pH of aquarium water. It is for this reason that you should buy rocks specially designed for aquariums.


Saltwater and freshwater aquariums are different and therefore have different requirements. Just like some fish can’t live in freshwater and saltwater and others can only live in freshwater, the same goes for rocks. The wrong type of rock in the wrong water can also affect the water, which can then harm your fish. You should always check the rocks you use are suitable for the type of aquarium you have.

Rocks for saltwater aquariums include Fiji Rock, Pukani Rock, Aquacultured Live Rock, Dry Rock and Tonga Branch Rock. Rocks for freshwater aquariums include Slate, Lava Rock, Petrified Wood, Mountain Stone and Quartzite.



When it comes to choosing the best stone for aquariums, there are many things to consider. Do you want natural or artificial stone? Something just for looks or looking for a solid foundation to start a reef tank?

Regardless of your needs, the Best aquarium rocks we’ve included in these reviews are among the best available. We’re confident you’ll find one that’s right for your aquatic landscape.