How to Properly Clean Fish Tank (Aquarium) Rocks

By Eddie Waithaka @aquariawise

How Do You Clean Rocks in A Fish Tank

You probably enjoy having a fish tank in your home. Not only is it a beautiful addition to any room, but it’s also a great way to relax and relieve stress.

However, your fish tank can quickly become a mess, and one of the biggest culprits of a dirty fish tank is the rocks.

Dirt from leftover food, plant matter, fish poop, and algae on your rock surface will rapidly become an eyesore if not cleaned properly and regularly.


In this essay, I’ll teach you how to clean fish tank rocks properly and keep your aquascape looking good.

Please see below!

Should You Clean Your Fish Tank Rocks

Fish tank rocks should be washed. If they are not too dirty, vacuum them with a vacuum kit similar to how you clean gravel or sand. However, if there is fish poop stuck to the surface or algae growing on the stones, you will have to retrieve the rocks from the tank for a wash with vinegar and water solution.

You can also clean your aquarium rocks with peroxide or bleach, though I prefer using these solutions when cleaning new aquarium stones collected outside or on a beach before placing them in the tank.

Clean your fish tank rocks using a vacuum kit once a month. Remove the stone from the tank and wash them only when they are murky with algae, food, or fish waste or when treating your fish for an infection.

Use hydrogen peroxide to disinfect your aquarium rocks, decorations, and plants to remove parasites and other disease-causing organisms from your fish tank.

How Do You Clean Rocks in A Fish Tank

As we’ve noted,…

One of the most important - but often overlooked - aspects of fish tank maintenance is cleaning the rocks. Fish poop and other debris quickly build up on the rocks and create an unsightly and unhealthy environment for your fish.

Fortunately, cleaning rocks is a relatively straightforward 3 step process, as shown below.

1.Remove the rocks from the tank and soak them in a bucket of water mixed with a cleaning agent such as diluted bleach. Vinegar will also do a perfect job cleaning aquarium rocks and is safer for fish tank use.

If you need to disinfect your fish tank rocks, you clean them with peroxide but ensure you rinse thoroughly to remove any residue before adding them back into the tank.

2.Let them soak for a few minutes, then scrub them with a brush to remove any built-up dirt or algae.

You can use an ordinary toothbrush to reach tight crevices within the rock structure and a scouring pad (with a course and rough sides) to remove slimy grime from the rock face.

Use a turkey buster to remove tiny dirt, such as fish poop, from tight spaces on the rocks, especially if you have porous aquascapes, like lava rock, in your fish tank.

3.Rinse the rocks thoroughly and return them to the tank. Ensure all vinegar, bleach, or peroxide residue is washed from the rocks before you place them back.

Do not use commercial detergent to clean aquarium rocks.

What Can You Wash Fish Tank Rocks With

There are several options when it comes to washing fish tank rocks. You can use water, vinegar, or peroxide. Each method has its own benefits and drawbacks, so choose the option suited to your needs. Avoid using soap, detergent, or any cleaning product with additives harmful to fish or aquarium plants.

Can You Clean Aquarium Rocks with Vinegar

You can clean your aquarium rocks with plain water and a sponge, but adding white-vinegar to the mix helps remove light and tough grime effectively without needing to scrub them too much.

Vinegar is best for cleaning algae or calcium deposits from fish tank rocks. The solutions loosen the dirt off the stone surface, making it easy to wipe off the residue with a sponge and water.

It is ideal for removing mineral deposits on fish rocks, even if you do not remove all microalgae buildup and stains.

Cleaning your fish tank rocks, plants, and surfaces with vinegar is safer than using bleach since white-vinegar (with no additive) is not as toxic to marine life. It is a weak acid that dissolves in water readily.

In the place of white-vinegar, you can also use other weak acids, such as citric acid to clean fisk tank rocks.

Cleaning Aquarium Rocks with Vinegar

Use vinegar to clean your aquarium rocks, artificial plants, and decor. You can also use it to dust and clean algae from live plants.

To clean fish rocks with vinegar,…

1.Add one part vinegar and one part water in a sizable bucket and mix to prepare a weak acidic solution. Remember to only use white-vinegar because it has no additives. Apple cider vinegar is not recommended.

2.Soak your rocks in the solution for an hour or two, but if you are cleaning new rock forms for your fish tank, soak them for up to 4 hours to remove all dirt, plus any bugs that may be residing in the crack.

3.Remove the rocks from the bucket after an hour, rinse them with clean water, then go in with an old toothbrush to remove algae and other solid debris from the stone surface.

4.Follow that with a scouring pad to remove slimy algae patches that the brush will miss. You can use a long and thin stick or metal, like skewers, to remove grime in tight or dip spots on the rock. A turkey buster will suck out any residual water in tight spaces.

5.Once you’ve removed all the dirt from your rock, rinse it in clean running water from a tap before you add it to your fish tank.

Cleaning Aquarium Rocks with Bleach

Cleaning aquarium rocks with bleach can be a daunting task but can be a breeze with just a little preparation.

The first step is to gather all of the necessary supplies. This includes a bucket, bleach, water, a scrub brush, and a rag or sponge.

The next step is to fill the bucket with water and add the bleach.

Add the aquarium rocks to the bucket (with the bleach solution) and let them soak for an hour or two. Be sure to read the bleach label to determine how much to use, but for the most part, one part bleach to nine parts water (10 percent bleach) is ideal for cleaning aquascapes like fish rocks and artificial aquarium plants.

After the rocks have soaked, use the brush to scrub them clean. Then, use the rag or sponge to polish them until they are clean.

And that’s it!

Your aquarium rocks are now clean and ready to use.

Please note bleach is harmful and can kill fish!

Too much bleach residue will dissolve your fish’s skin and gills, making it difficult for the fish to breathe. The bleach will also upset the fish’s stomach, causing it to have abdominal upsets and eventually die.

So rinse out bleach from your aquarium rocks before you put them back into the tank.

Tropical aquarium fish are particularly susceptible to bleach, so it’s best you use it to cure dry and live rocks for marine and reef tanks. Only use bleach to clean freshwater fish rocks if white-vinegar is not available.

Cleaning Aquarium Rocks with Hydrogen Peroxide

Another way to clean aquarium rocks is by using hydrogen peroxide. This method is very effective in removing any build-up of algae or dirt and disinfecting the fish tank stones, especially pieces retrieved from ocean and river shores.

Hydrogen peroxide is stable and will clean and disinfect your rocks, then dissolve in water to give out oxygen with no residue harmful to fish.

To clean the aquarium rocks with hydrogen peroxide, you will need a bucket, some hydrogen peroxide, and a scrub brush. Fill the bucket with water and add the hydrogen peroxide three parts to seven (3 percent Peroxide). Stir the mixture until the hydrogen peroxide is completely dissolved. Add the rocks and let them soak for about an hour. Then, use the brush to scrub the stone, rinse them with clean water, and let them dry.

You can also use a spray bottle to soak your rocks with the hydrogen peroxide solution (3 percent) and let them dry in the sun until the H202 turns into oxygen before placing them in your fish tank.

Bleach is strong and more effective at killing bugs and parasites in aquarium rocks, but peroxide (and vinegar) is safer for cleaning aquascape for freshwater fish tanks.

Vinegar is my first option (and peroxide my second choice) for cleaning rocks from my fish tank of algae, poop, plant matter, and leftover fish food.

I only use bleach to clean new stones I’ve retrieved from a beach or outside, and only if they are very dirty or bug-gy.

How to Clean Aquarium Rocks of Algae

Aquarium rocks can become covered in algae over time, which is unsightly and can reduce the water quality in the tank. However, there are a few ways to clean algae off fish tank stones.

One way to clean algae off aquarium rocks is to use a scrub brush. You can use a brush designed for cleaning aquariums or a regular scrub brush. If you use a regular one, ensure you clean it thoroughly before use, as detergents and soap from household cleaning can be transferred back to your aquarium.

Another way to clean algae off aquarium rocks is to use a water jet.

A jet with adequate pressure will effectively clean algae off aquarium rocks if you soften the algae by soaking the stones in a vinegar solution and dislodging it with a brush.

Ensure caution when using a water jet because it can be perilous if not used appropriately.

If the alga on your aquarium rocks is not too thick, place it under a running tap and use a brush to remove it.

For medium-density algae (too dense for a tap stream but not enough for a water jet), fix a hose on the tap, squeeze the other end to make a manual jet, and direct it on the rock to remove the grime. Use a brush to loosen the algae.

Well, thats all for this post!

Let’s link up on the next fish🐠__y post.

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