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The Best Aquarium Rocks For Your Freshwater Or Marine Tank

Choosing the best aquarium rocks depends on your tank type and fish, as some rocks can affect your water chemistry. So read on to find out what to look for!

By Julie Millis
Last updated on

Disclaimer: This article contains affiliate links. We may be compensated if you make a purchase after clicking them, at no extra cost to you.

Best For Planted Tanks

Lifegard Dragon Rock

Best For African Cichlids

Lifegard Smoky Mountain
best aquarium rocks

When looking for the best aquarium rocks you need to consider important factors like your tank type and water chemistry. Some rocks contain calcium carbonate which can raise your pH and water hardness, and others like live rock are only for marine tanks.

We’ve assessed the best aquarium rocks to help you find the right type. And we chose Small World Natural Slate as best for building caves in a freshwater tank, while our top choice for saltwater is Caribsea LifeRock for its ability to kick-start your new reef tank!

But we’ve also included a range of full rock kits, pebbles, and replica rocks at different price points, so whatever your set up, it’s covered!

Let’s take a look at the list…

  1. Best For Building Natural Structures: Small World Natural Slate Stone
  2. Best For Planted Tanks: Lifegard Aquatics Dragon Rock Kit
  3. Best For African Cichlids: Lifegard Aquatics Smoky Mountain Rock Kit
  4. Best Premium Rock Kit: Lifegard Aquatics Redwood Petrified Stone Kit
  5. Best For Bettas & Delicate Fish: Sackorange Aquarium Gravel River Rock
  6. Best For Natural Color: biOrb Moss Pebbles
  7. Best For Territorial Fish: Penn-Plax Deco-Replicas Ornaments
  8. Best Realistic Rock Hideout: Penn-Plax Reptology Shale Step Ledge
  9. Best Reef Live Rock Alternative: Caribsea LifeRock
  10. Best Dry Base Rock: CaribSea South Sea Base Rock

Best Aquarium Rocks Reviewed

We’ve considered the most important factors when it comes to choosing the best aquarium rocks for your tank. This includes whether they will affect your water chemistry and suitability for freshwater or saltwater tanks.

1. Small World Natural Slate Stone


  • Rock Type: Slate (metamorphic)
  • Size & Weight: Each stone 2.0 to 3.0 inches, 2.0 or 5.0 lbs pack
  • Aquarium Type: Mainly freshwater
  • Affects Water Chemistry?: No
  • Best For: Building Natural Structures

These natural slate stones from Small World are flat, stackable, and very stable, making them one of the best aquarium rocks to build structures like arches or caves. And if you use aquarium glue they’ll hold for several years.

They are inert and won’t change your water’s pH or hardness, making them suitable for most species including those that prefer softer water, like Gourami’s. While they’re more commonly used in freshwater tanks, you can also use them in a saltwater aquarium.

We’ve chosen the smaller slate stones here. The 2.0 lbs bag contains around 30 to 40 stones roughly 2.0 to 3.0 inches in size, which is perfect for a 5 gallon or 10 gallon tank. You can also choose the 5.0 lbs bag if you want to create structures for a slightly larger 20 gallon aquarium

But if you have a bigger 40 gallon tank we’d recommend the 10 lbs Large Stones, which are about 5.0 to 7.0 inches and come in bags of around 8 rocks. And while they’re solid, they’re quite easy to break into smaller stones if you use a chisel to cut along the grain. 

Bear in mind, slate can have sharp edges so we don’t recommend these rocks if you have fish with delicate fins like a betta or fancy goldfish. And as many users report, do make sure you clean them well to avoid excess dust in your tank.

2. Lifegard Aquatics Dragon Rock Kit


  • Rock Type: Clay-based (sedimentary)
  • Size & Weight: 10G kit: 3 to 6”, to 6 to 9” rocks, 15 lbs; 25G kit: 3 to 6” to 9 to 15”, 25 lbs
  • Aquarium Type: Freshwater
  • Affects Water Chemistry?: No
  • Best For: Planted Tanks

Dragon or Ohko rock is a natural, sedimentary rock full of striking holes and cavities. This makes it look beautiful in your freshwater tank and gives extra surface area for beneficial bacteria, which break down ammonia in your tank.

These holes also make Dragon rock one of the best aquarium rocks for planted tanks as you can use them to anchor plants like Anubais or Java Fern. A clay-based rock, Dragon rock is inert and won’t affect your pH or hardness, so you can use it with most fish and invertebrates.

The Lifegard Aquatics Dragon Rock 10 G Kit comes with around 6 small rocks of about 3.0 to 6.0 inches and 2 medium of 6.0 to 9.0 inches. This is plenty for a 20 x 11 x 12 inch 10 gallon tank and even a 20 gallon tank. If needed you can gently shape these rocks with a chisel too.

For bigger tanks, the 25G kit gives you about 6 small rocks, 2 medium, and one larger 9.0 to 15.0 inch rock. Again, we found a kit this size still looks good in a 36 x 15 x 16 inch 40 gallon tank. So you actually get a lot for the price.

Each rock comes individually wrapped in plastic, so although they can be fragile you shouldn’t get any breakages in transit. They do come with lots of clay in the holes though, so we recommend soaking for 1 or 2 days before you gently clean with a small brush.

3. Lifegard Aquatics Smoky Mountain Rock Kit


  • Rock Type: Seiryu (metamorphic)
  • Size & Weight: 10G kit: 3 to 5” & 5 to 8” rocks, 15 lbs; 25G kit: 3 to 6” & 6 to 9”, 25 lbs
  • Aquarium Type: Freshwater
  • Affects Water Chemistry?: Yes
  • Best For: African Cichlids

A similar collection from Lifegard Aquatics is the Smoky Mountain Rock Kit, which contains Seiryu stone. With their blueish-gray color and varied shapes and sizes, you can create a stunning look for your freshwater tank.

Be aware that Seiryu is limestone-based and contains calcium carbonate, so will raise your pH and water hardness. So it can be one of the best aquarium rocks if you need harder water for certain African cichlids or Killifish.

The 10G kit weighs around 15 to 16 lbs and comes with around 5 to 7 rocks. Three to five smaller 3.0 to 5.0 inch, and two medium 5.0 to 8.0 inch ones. Again, we found this is actually plenty for a 24 x 12 x 17 inch 20 gallon tank so given the price you get good value here too.

You’ll get around 8 rocks in the 25G kit, with six smaller 3.0 to 6.0 inch and two larger 6.0 to 9.0 inch stones. This will look great in a 24 x 18 x 18 inch 30 gallon aquarium, or even a 40 gallon tank if you own one.

Bear in mind these rocks are also quite jagged with sharp edges and cracks, so again we don’t recommend if your fish have long-flowing fins. But overall they are a gorgeous addition to a harder water tank.

4. Lifegard Aquatics Redwood Petrified Stone Kit


  • Rock Type: Petrified wood
  • Size & Weight: 25G kit: from 4.0 to 16.0 inches, 21 to 25 lbs
  • Aquarium Type: Freshwater
  • Affects Water Chemistry?: No
  • Best For: Premium Rock Kit

Our third collection from Lifegard Aquatics is the Redwood Petrified Stone Kit. This is actually fossilized wood, formed when minerals like silica or calcite penetrate and slowly replace the original wood [1]. And it leaves these beautiful stones with their brown and red shades.

This is a premium 25G kit for freshwater tanks, and that’s reflected in the price. But you do get around 14 stones, with one larger 16.0 inch rock, 2 or 3 medium ones, and 10 small of about 4.0 inches. We found this enough for a 30 gallon or even a 40 gallon tank at a push.

These petrified stones are completely inert and won’t affect your water parameters, so you can use them with confidence even if your tank has very soft water. They are also not too rough so safe with most types of fish.

And while they can be fragile to handle, they come individually wrapped and double-boxed. So you shouldn’t have any issues with breakages on delivery. Overall this is a fantastic set reflected by the high praise from owners for their striking colors and appearance.

5. Sackorange Aquarium Gravel River Rock


  • Rock Type: Natural river pebbles
  • Size & Weight: Single stone up to approx.1.0 inch, 2.0 lbs bag
  • Aquarium Type: Freshwater
  • Affects Water Chemistry?: No
  • Best For: Bettas & Delicate Fish

River stones or pebbles can be some of the best aquarium rocks for smaller tanks. This 2.0 lbs bag from Sackorange contains just enough to act as colorful highlights to the main substrate in your 5 gallon fish tank.

The stones are smooth and polished, making them safe to use if you have fish with flowing fins such as a betta. They’re also inert with no chemical coatings, so won’t affect the hardness or neutral pH preferred by these fish.

And although the sizes vary slightly, each stone is around 1.0 inch, meaning if you have algae eaters like plecos or molly fish they can’t get them caught in their mouths in the same way as gravel.

Even though these stones are smooth, do check for any shaper ones and remove them before using them in your tank. But overall owners praise these pebbles for their natural look and affordable price.

6. biOrb Moss Pebbles


  • Rock Type: Replica moss-covered rocks
  • Size & Weight: Largest 2.7 x 1.8 x 1.6 inches, 0.8 lbs
  • Aquarium Type: Freshwater
  • Affects Water Chemistry?: No
  • Best For: Natural Color

These replica moss-covered rocks from biOrb are fantastic if you want to add some natural color to your aquarium. You can use them in freshwater and saltwater tanks, although they do tend to look better in freshwater setups.

Although lightweight, they are heavy enough to sit well at the bottom of your tank. So you won’t have any issues with them floating up. And the plastic replica moss looks incredibly realistic, so will help give your tank a natural look.

The moss coating is very soft, non-toxic, and inert. So these rocks won’t affect your pH or hardness and are also safe to use with your betta or other delicate fish. They can attract a build-up of algae in time, but this can be easily removed by soaking in a weak bleach solution.

You get 5 rocks of various sizes in the set, with the largest around 2.7 x 1.8 x 1.6 inches. So they’re big enough to look great in a 10 gallon tank. Or you can use them in a smaller nano aquarium where their size can make them a gorgeous focal point.

Although one or two owners report some of the moss fibers can come loose, if you soak them for 1 to 2 days before use you should avoid this. And the majority of reviewers give these pebbles praise for their realistic appearance and ability to sit well in their tank.

7. Penn-Plax Deco-Replicas Ornaments


  • Rock Type: Replica granite cave
  • Size & Weight: Large 6.0 x 4.5 inches, extra-large 7.0 x 6.0 inches, 5.0 lbs
  • Aquarium Type: Freshwater/ Saltwater
  • Affects Water Chemistry?: No
  • Best For: Territorial Fish

Penn-Plax Deco-Replicas are a series of replica stone caves that are great hideouts for your fish. We’ve chosen the 2 piece large & extra-large set here, but they also come in small, large, 2 piece small & medium, and a full 8 piece set of varying sizes.

The large cave measures 6.0 x 4.5 inches, and the extra large is 7.0 x 6.0 inches, so they’ll fit well if you have a bigger aquarium of around 30 gallons or upwards. But if you choose the small size option, at 2.4 inches, this will fit nicely in a 3 gallon tank.

They are produced using coarse granite sand and are completely inert, so you can use them in freshwater or saltwater tanks without affecting your water parameters. And the large holes make them great hideaways for mid-size territorial fish like Kribensis.

The caves have a slightly flattened surface at the top and are very sturdy when you stack them together. You can even mix and match with caves of different sizes in the series, so you can completely customize your set to suit your tank and fish.

We found these caves have a few sharp edges around the openings which needed sanding, so we wouldn’t recommend them for delicate fish like bettas. But overall many owners praise them for being sturdy, easy to clean, and a beautiful addition to their tank!

8. Penn-Plax Reptology Shale Step Ledge


  • Rock Type: Resin-based replica shale hideout
  • Size & Weight: Medium: 7.0 x 9.0 x 3.5 inches, 0.8 lbs
  • Aquarium Type: Freshwater
  • Affects Water Chemistry?: No
  • Best For: Realistic Rock Hideout

The Penn-Plax Reptology Shale Step Ledge has a slightly textured, painted finish making it look incredibly realistic. Yet as it’s made from non-toxic, aquarium-safe resin it won’t alter your water parameters and is safe for your aquarium fish as well as small reptiles.

While you can use it in a saltwater tank, it looks more natural in a freshwater aquarium. And although it’s made of resin, it feels very sturdy, especially at the base. So it will sit well on your substrate without any movement.

This hideout comes in small, medium, large, and extra-large sizes so you can choose one to fit anything from a nano aquarium to a 55 gallon tank. We chose the medium size which at 7.0 x 9.0 x 3.5 inches fits a 20 gallon tank well.

It has 4 entrance holes with the smallest at 2.5 x 1.5 inches, so makes a fantastic swim through and hideout for smaller fish like tiger barbs.

Some owners have reported sharp edges on this hideout, particularly around the base. So although we didn’t find them, do inspect the item first and file away any you find. But overall many owners praise this hideout for its realistic design and value for money.

9. Caribsea LifeRock


  • Rock Type: LifeRock (marine bacteria-infused dry rock)
  • Size & Weight: Varies approx. 10.0 to 15.0 inches, 40.0 lbs
  • Aquarium Type: Saltwater
  • Affects Water Chemistry?: Yes
  • Best For: Reef Live Rock Alternative

Caribsea LifeRock is a fantastic alternative to live rock if you’re setting up a reef tank. It’s an aragonitic dry rock containing 97% calcium carbonate, which buffers the water and supports coraline algae and corals as your tank matures.

Unlike real live rock which can contain hitchhikers, this dry rock is pest free having been pre-cured before sale. It’s infused with beneficial marine bacteria which are dormant when dry, but help cycle your tank when you add the rock.

We chose the 40.0 lbs box which contains 6 to 8 rocks although this can vary. The size can differ too, but the rocks mainly range from 10.0 to 15.0 inches, so are great if you have a saltwater tank of 40 gallons or above. You can also choose the 20.0 lbs box for smaller tanks.

As these rocks have already been cured they are easy to clean before you set up your tank, just give them a thorough rinse to remove any dust. Although some users report the color can fade, most praise LifeRock for its ease of use, and gorgeous appearance.

10. CaribSea South Sea Base Rock


  • Rock Type: Dry base rock
  • Size & Weight: Varies approx. 6.0 to 8.0 inches, 10.0 lbs
  • Aquarium Type: Saltwater/ hard water freshwater
  • Affects Water Chemistry?: Yes
  • Best For: Dry Base Rock

CaribSea South Sea Base Rock is a similar dry rock formed from calcium carbonate. But unlike their LifeRock, it doesn’t contain marine bacteria and so is suitable if you have a saltwater or a hard water freshwater tank.

In fact, it’s one of the best aquarium rocks if you have African cichlids as the calcium carbonate will help stabilize your pH at around 8.0 which is perfect for them. It also has about 50% porosity giving a fantastic surface area for beneficial bacteria to colonize.

You generally get about 3 rocks in the 10.0 lbs box, although this can vary. And the sizes can differ greatly too but are around 6.0 to 8.0 inches. So it’s great if you own a small saltwater aquarium, or a 10 gallon tank. But for a 20 gallon tank you may need another box.

Note these rocks can be difficult to clean, and we recommend you soak them in clean water for at least 48 hours before use, particularly for a freshwater tank. This will prevent minerals leaching into your water and making it cloudy.

But overall owners give these base rocks great praise for being a beautiful addition to their tank and helping to stabilize a hard water environment.

Why Do You Need The Best Aquarium Rocks In Your Tank?

Adding the best aquarium rocks to your tank not only makes it look beautiful but also benefits your fish and their ecosystem in several ways.

Aquarium fish and rocks
  • Mimics Nature: Using the best aquarium rocks in your tank helps create a natural environment for your fish, helping them feel comfortable and secure. 
  • Provides Shelter: Rocks provide hiding places and interest for your fish. Studies in Zebrafish have shown rocks increase exploratory behavior and reduce stress [2].
  • Habitat For Microorganisms: The best aquarium rocks provide the right surface for beneficial nitrifying bacteria and other microorganisms to colonize. These break down harmful ammonia into less harmful nitrates via the nitrogen cycle.
  • Food Source: Algae will often form on rocks in your aquarium. This is an important part of some fish’s diets such as freshwater Otocinclus, or saltwater fish like Surgeonfish [3].
  • Stabilize Water Parameters: Calcareous rocks, composed of calcium carbonate, can be used to raise your pH and hardness levels. This can be useful in helping stabilize your saltwater tank’s water parameters.

The Main Types Of Aquarium Rock

The best aquarium rocks for your tank will depend on whether you own a freshwater or saltwater aquarium, and the water hardness your fish prefer.

The Three Popular Types Of Freshwater Aquarium Rock

While you can use some of these in a saltwater aquarium, below are the three best aquarium rock types for freshwater tanks. Do take care when selecting them though, as not all may be suitable for your tank.

Igneous Rock

basalt rock

These are formed when molten rock, either magma or lava, quickly cools and solidifies. Igneous rocks can be a gorgeous addition to your aquarium as the fast cooling often gives them a glassy look [4].

Most igneous rocks, such as basalt, are inert so you can use them in your fish tank without altering the water chemistry or pH. They are also incredibly dense and hard-wearing so will last for the life of your tank.

Sedimentary Rock

Dragon rock on white background

As the name suggests, these rocks are formed from deposits of sediment that are compacted together [5]. Sedimentary rocks tend to be quite porous and so provide a good surface for beneficial bacteria to colonize and support your tank’s nitrogen cycle.

But they can erode more easily than other types, particularly if you have a high water flow in your tank. Many of these rocks, such as limestone, also contain minerals like calcium which will raise your pH and make the water harder.

Metamorphic Rock

slate on white background

Metamorphic rocks start life as igneous or sedimentary types but are re-formed through extreme heat and pressure making them incredibly dense and hard [6]. Make sure you choose these rocks carefully. Slate, for example, is generally inert and won’t affect your water chemistry. 

But Seiryu stone, another common type, is limestone-based and contains calcium carbonate which will raise your pH and hardness. This can be a good choice if you keep Lake Malawi cichlids that prefer harder water and a pH of around 8.0.

The Main Types Of Saltwater And Reef Aquarium Rock

Although you can include some of the rocks above in a saltwater aquarium, the best aquarium rocks for a full reef tank are specialized reef rocks. These form a base for adding soft corals and generally come in two types: live rock and dry rock.

Live rock is actually fragmented coral that has been naturally colonized by marine bacteria and other organisms. It’s harvested and cured before sale to remove decaying material that would otherwise bring toxins such as ammonia into your tank.

Dry rock is usually an aragonitic or oolitic marine limestone that is again cured before being sold to aquarists. Be aware that dry rock can take longer to cycle than live rock, often up to 6 weeks. It’s this biological cycling that introduces the beneficial bacteria needed for your reef tank.

Aquarium Rocks That Change Water Chemistry

As we’ve touched on above, if you want to raise the pH of your water along with its carbonate hardness (KH) and general hardness (GH), the best aquarium rocks are calcareous rocks, such as limestone, marble, or dolomite.

These rocks will make your water even harder if you use them alongside a CO2 system because of the carbonic acid that is produced from the CO2. This tiny amount of acid reacts with rocks like limestone releasing more calcium.

If you don’t want to change your water parameters the best aquarium rocks to use are inert ones like slate or basalt. While these rocks can’t make your water any softer you can use driftwood, peat moss, or a reverse osmosis (RO) filter to do this.

Testing Aquarium Rocks For Carbonates

It’s a good idea to test your chosen aquarium rock for carbonates if you’re not sure whether or not it will harden your water. Liquid oak extract or ‘pH Down’ will easily allow you to do this.

These products test for lime in the rock. Simply add a few drops on the surface and if there’s no reaction there’s either no or very little lime. But if the rock foams it contains calcium carbonate and will cause your aquarium water to become harder.

How To Choose The Best Aquarium Rocks

There are several factors when choosing the best aquarium rocks for your tank. Let’s take a look at the main ones you should consider.

Discus in fish tank

Your Aquatic Animals And Plants

Start by researching your fish and choosing the best aquarium rocks based on whether they prefer softer or harder, more alkaline water. Discus, for example, prefer softer, acidic water with a pH of around 6.0 and KH of 18 to 70 ppm, so choose inert rocks such as granite.

Others, like some African cichlids and Rainbowfish, prefer moderately hard water. So you can choose calcareous rocks like limestone or Seiryu stone.

Similarly, there are some aquatic plants like Eriocaulon cinereum that are more adapted to soft water. But many plants will tolerate a range of water conditions, and plants like Java Fern and Vallisneria will do well in alkaline conditions, so calcareous rocks are fine.

Safety, Coatings, And Rough Edges

Check that the rocks you are considering are aquarium safe and don’t have coatings or polishes that could be toxic to your fish. The best aquarium rocks are from brands that are specifically designed for fish tanks, rather than general garden or decorative stones.

Many brands also offer plastic, resin-based aquarium rocks and some even produce man-made rocks formed from compressed sand. Again, as long as these are from reputable aquatic manufacturers using non-toxic materials they won’t harm your fish.

Look out for sharp or rough edges too. Some of the best aquarium rocks are tumbled and polished to remove these. But some, like Dragon rock, have sharp edges as part of their appeal. So avoid if you have fish with delicate fins like fancy goldfish or betta fish.

Size And Amount Of Aquarium Rock

You sometimes need to be careful with gravel or very small pebbles under ¼ inch as some fish chew on or even ingest these. But with larger aquarium rocks the main considerations are aesthetics and the overall fit for your fish tank.

The best aquarium rocks give their weight on the packaging, along with suitability based on the number of gallons your tank holds. Some even come as kits with 5 or 6 rocks of different sizes that you can arrange in your tank.

Just make sure you don’t overload your tank with aquarium rocks. Remember your fish need plenty of swimming space as well as room to establish their territory.

Appearance, Structure, And Shape

Adding the best aquarium rocks to your tank can make a dramatic difference to its look. If you have a natural theme you could consider darker aquarium rocks like basalt, or lighter brown rocks like Redwood stone.

Some rocks such as Dragon rock also tend to be taller and more upright. Whereas the flatter shape of slate makes it good for stacking and building structures. Man-made aquarium rocks and caves can also provide great hiding places where your fish can feel safe and secure.

Biofiltering Capabilities

In addition to the biological media within your filter, the substrate in your tank and your aquarium rocks provide fantastic surfaces for beneficial nitrifying bacteria. The more these bacteria thrive, the better the breakdown of ammonia, and the cleaner your water.

The best aquarium rocks provide a good surface for these bacteria to colonize. Often these can be porous rocks like petrified stone, or rocks with an uneven surface like Seiryu stone.

Price And Value For Money

It’s important to factor in your budget when choosing aquarium rocks. The best aquarium rocks, particularly larger, natural ones like slate and Dragon rock, can be expensive. Price can vary depending on the type, but these rocks for a 20 gallon tank can be around $60 to $100 or more.

Man-made resin aquarium rocks and smaller pebbles can be significantly cheaper, and if you are on a budget you can still create a beautiful tank with these.

rocks in flowing stream

Source And Using Rocks Found In Nature

If you own a saltwater aquarium you are most likely to need live or dry reef rock. Your best source for these are reputable aquarium brands, such as CaribSea, that will have properly cured and conditioned them.

For freshwater aquariums, again, the best aquarium rocks are generally those purchased from aquarium brands. But you can use some rocks sourced from nature if you take extra care.

Make sure you can identify the rocks you find correctly, and test them for carbonates so you don’t accidentally cause your water to become more alkaline. You’ll also need to clean them correctly to reduce the risk of disease entering your tank.

Cleanliness: Washing and Conditioning Aquarium Rock

The best aquarium rocks from specialized aquarium brands will usually only need a light cleaning before use in your tank. This particularly applies to saltwater live and dry rocks as these are usually pre-cured by the supplier.

We’ve outlined three of the most common cleaning methods below:

  • Rinsing With Water: If you’ve sourced specialized aquarium rocks from a known brand you can usually just scrub them gently using a brush under a tap. This helps to remove dust and debris from shipping.
  • Soaking In Water: You can soak your aquarium rocks in distilled water for 1 or 2 days if you want to give them a deeper clean. This can be a good method for rocks with lots of holes or cracks such as Dragon rock.
  • Soaking With Bleach: You should only need to do this with older rocks that may have a build-up of black algae. Use 1 part domestic bleach to 9 parts water and soak your rock for 1 or 2 days. Then soak in tap water for a further 2 days before allowing to dry.

Some aquarists recommend boiling aquarium rocks to kill unwanted microorganisms. We tend to avoid this method as it can sometimes crack your aquarium rocks and they need to be completely cooled before placing in your tank.

Our Verdict

When looking for the best aquarium rocks for your tank make sure you choose the right type for freshwater or saltwater, their effect on your water chemistry, and that they won’t damage delicate fins.

We found Small World Natural Slate Stone to be the best aquarium rocks for building caves and arches in a freshwater tank. Or the Lifegard Aquatics Dragon Rock Kit is a fantastic full set to bring interest to your planted aquarium.

And for a reef tank, the best aquarium rocks are Caribsea LifeRock as the infused marine bacteria will help kick-start your tank without the worry of pests you may find in live rock!


We’ve provided the answers to some of the most frequently asked questions when it comes to choosing the best aquarium rocks. Check them out here!

What Are The Best Aquarium Rocks For A Freshwater Tank?

Small World Natural Slate Stone are some of the best aquariums rocks for making structures in a freshwater tank. Or the Lifegard Aquatics Dragon Rock Kit is great for planted tanks!

What Are The Differences With Saltwater Aquarium Rocks?

Saltwater and reef tank rocks like live and dry rock contain beneficial marine bacteria and generally raise alkalinity. They are not suitable for freshwater tanks.

Can I Use Rocks Found Outside In My Aquarium?

It’s generally safer to source the best aquarium rocks from reputable aquarium brands. But if you do use rocks from nature make sure you identify them and clean them well.

How Should I Clean My Aquarium Rocks?

If you’ve sourced the best aquarium rocks from well-known aquarium brands give them a light rinse under tap water. Older rocks can be cleaned with a dilute bleach solution.

Photo of author
Julie Millis
Julie has been involved in aquatics for over 15 years. She is passionate about freshwater and saltwater tanks. Julie loves helping with all your fish-keeping questions!

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