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Cleaning Aquarium Rocks with Vinegar: 3 Methods + 5 Back-Ups

Cleaning Aquarium Rocks with Vinegar: 3 Methods + 5 Back-Ups

Water and tank glass aren’t the only parts of the aquarium that need to be cleaned. You need to be mindful of decoration, too! Cleaning aquarium rocks with vinegar might be one of the easiest methods you can find.

Clean decorations mean happy fish! How many times did you change the water and scrub the glass, just to have your tank water dirty in a matter of days? Chances are you’ve forgotten about the decorations, and this includes aquarium stones and rocks.

Fortunately, this isn’t a difficult task. All you need is a bit of apple cider vinegar or distilled malt vinegar and your rocks will be as good as new!

Yes, you’ve read that correctly. Cleaning aquarium rocks with vinegar is possible, and it might be one of the most effective methods you can find. In fact, there are 3 different ways you can use vinegar to clean your rocks and other decorations!

If you want to clean aquarium rocks of algae, waste, and other debris, keep on reading!

How to Clean Aquarium Rocks with Vinegar

Aquarium decorations, such as rocks, need to be in top-notch condition to ensure the happiness of your tank inhabitants. They are especially important for shy creatures, such as ninja shrimp or blue velvet shrimp, that love to have plenty of hiding spots. 

However, fish waste, food leftovers, and green spot algae can build up on the rocks. Not to mention all the hard water stains and mineral deposits that are common if you use tap water! Yes, I’m talking about that white residue at the top of your tank.

Using vinegar is an effective way to make sure your tank decorations are clean and disinfected. However, there is a right and a wrong way to complete this task. 

I’ll share with you three methods for cleaning aquarium rocks with vinegar that I’ve personally tried out! This way, you’ll know they truly work.

Keep in mind that you need to take the rocks out of the tank before cleaning them. 

Also, don’t use vinegar to clean rocks made out of calcium carbonate. Combining such rocks and vinegar might lead to a chemical reaction that will greatly damage the rocks.

Let’s get started!

Method 1: Vinegar Dipping

vinegar dipping method to clean aquarium rocks
Photo: Youtube

If you’d like to clean a fish tank with vinegar, the easiest method is dipping. No, not in pure vinegar.

What you need to do is to create a solution made out of one part vinegar, one part water. Pour it in a plastic bucket, then place the stones in it and leave them inside the solution for about 24 hours. Make sure the stones are dipped entirely and that they are under the water level.

Once the time has passed, thoroughly rinse the stones and allow them to dry completely

The 1:1 vinegar solution is great for dissolving green algae, but also any hard stains and discoloration. This will leave your stones clean and shiny.

You can also dip aquarium plants inside the same solution. A quick dip won’t cause them any harm, but it will keep them clean.

However, this method does take a while, as you’re required to leave the rocks inside the solution for an entire day. If you’re looking for a quick fix, this isn’t it.

Method 2: Scrubbing

This method takes a bit more effort than the previous one, but it is much quicker. 

What you’ll need is pure vinegar and a new toothbrush. I’d avoid using used brushes as they might not be harsh enough to fully complete this task.

Dip the toothbrush into vinegar, then use it to scrub the rocks. Strong vinegar will dissolve algae and a harsh brush will remove them from the rocks. All it’ll take is a quick scrub and your rocks should look sparkly clean!

The downside of this method is that it takes a long time. You’ll need to scrub each rock, one at a time! While it’s still faster than the first method, you’ll have to be the one to do all the work, compared to simply leaving everything overnight.

If you’re afraid that the vinegar will damage the rocks, you can also use the solution with the 1:1 vinegar to water ratio. However, it might not be as effective. The goal is for vinegar to be strong enough to remove all algae without any soaking.

You can also combine this method with the first one if there happened to be some algae left after the soaking.

Another good use of vinegar and a toothbrush is to clean the aquarium glass. You’ll have a pristine tank in no time!

Method 3: Add Salt

table salt to add with vinegar for cleaning aquarium rocks

Finally, if nothing else works, the best strategy might be to combine vinegar and table salt. 

These two solutions make a strong disinfectant. When combined with agents such as sodium bicarbonate, they can even be used to clean filters, aquarium siphons, or tank glass!

Add some table salt to vinegar. Sea salt will work just as well, but it might be a bit more costly.

Dip the rocks for a short while in this solution. You might distill it with some water, but most rocks will be fine without this. Such a solution will kill any spores and algae on the rocks.

Next, take a toothbrush or a sponge and dip it into a vinegar salt solution. Use it to scrub the rocks. Salt will act like a fine grip, keeping the rocks polished and adding more scrubbing power.

Keep in mind that you should n’t use anything with salt on acrylic aquariums. Salt might scratch acrylics, ruining your tank.

Is Vinegar Safe for Aquariums?

Fish are delicate creatures and it doesn’t take much to ruin their health, or worse. This is why many aquarists are careful with what they use for tank maintenance – as they should be.

Solutions such as vinegar might kill your tank inhabitants if used incorrectly. However, if you use it in the way I’ve described, the chances of hurting your fish are very small, almost non-existent.

Vinegar is an acidic solution due to high levels of acetic acid,a weak acid that gives it the recognizable taste. As such, it can be used to lower the pH levels of your tank.

However, if you use too much vinegar, you might make your tank water too acidic. This can be extremely harmful to the fish, especially saltwater species that prefer higher pH levels.

Not just that, but snails are especially susceptible to damage done by low pH levels. If you have snails, you need to be very careful. 

Vinegar will also attack aquarium’s microorganisms. This includes beneficial bacteria. Make sure to rinse anything you’ve cleaned before returning it to the tank.

Either way, always make sure to dilute the vinegar when using it for cleaning purposes. Also, use testing strips to monitor pH levels.

If you notice your alkalinity levels have dropped below 6.8, you might want to use some of the methods for raising your pH.

Also, always make sure the vinegar is natural, without any added colors. 

What Can I Clean My Fish Tank Rocks With?

fish tank with clean rocks

If, for any reason, you don’t want to use vinegar, don’t worry. This isn’t the only existing cleaning method.

Sure, you can buy chemical solutions and gravel vacuums designed especially for this task. However, harsh chemicals come with their own risks. Not to mention you might spend a lot of money on them!

Keep in mind that there are some chemicals and items that should never come near natural rocks. This includes:

  • Baking soda. Sodium bicarbonate is rather caustic, so it isn’t safe to be used on natural rocks. 
  • Soap and detergent. These cleaning products are highly toxic to fish, so never use them for items that will go into the water.
  • Pure bleach. While the bleach method is highly effective, pure bleach might be too strong. Also, some bleaches can cause harm even in trace amounts.

Of course, no matter what option you choose, it’s important to take the rocks and other decorations out of the aquarium before cleaning them.

Here are some alternative methods for keeping your aquarium rocks clean with common household items:

Hot Water

The easiest cleaning method is to use plain hot water and a clean sponge to remove any algae from aquarium rocks and other decorations. 

Rinse the rocks with hot tap water. For a stronger effect, soak them for a few minutes. This will soften any algae and fish waste buildup without causing harm to the rocks. 

Next, scrub it with a toothbrush, sponge, or even a wet cloth. This should remove most or even all of the algae on the rocks. 

Keep in mind that this usually isn’t enough for thick, persistent buildup. 


Bleach solution is known as a cleaning agent for many items. You can even use bleach baths to clean live plants!

Put the 10% bleach inside a plastic bucket and mix it with clean tap water. You want to make a one-part bleach, nine-part water solution

Next, soak the rocks in the bucket. Let them foam for 10 to 15 minutes. After you take them out, rinse them with tap water. If needed, scrub them gently with a toothbrush or a sponge.

This should remove even the most persistent algae.

Hydrogen Peroxide

Hydrogen peroxide is one of the most common bleaching agents. Still, you might want to use them in a slightly different way.

Take 3% hydrogen peroxide and put it in a spray bottle. Spray it on the rocks and let them foam. You can leave the hydrogen on for up to a few hours. Don’t worry – it won’t harm the natural rocks.

Rinse them with hot water and scrub them a bit. Your rocks will be as good as new!


You can use scrapers or a sharp razor blade to physically remove any algae from your tank. This method is commonly used by aquarists who want to have their tank glass crystal clean.

This is a straightforward method that doesn’t need any further explanations.

However, if you’re not careful enough, you might scratch the rocks and damage them. This is especially risky if your rocks are made out of softer minerals, such as opal or calcite. 

Also, this method can take a very long time, as you’ll need to scrape everything one rock at a time.


Toothpaste is a good solution for most natural rocks, as long as they aren’t composed of soft minerals. It works best when used on moderately hard minerals.

This isn’t a complicated method. Put a bit of toothpaste on a toothbrush and scrub the rocks until they are clean. 

Most kinds of toothpaste use abrasives that are silica derivatives. In fact, abrasives should always be the main component of toothpaste. They will clean rocks in the same way they keep your teeth clean.

In addition to this, toothpaste can be used to remove scratches on most glass and acrylic tanks and other smooth surfaces.

Final Words

Keeping the tank decorations clean is just as important as cleaning any other part of the tank. They are a part of a delicate ecosystem that you need to take care of.

Cleaning aquarium rocks with vinegar is a safe and effective method most of us can complete without any hassle. However, there are a few things to be mindful of. 

Even though vinegar is deemed safe to use, you should still make sure to carefully rinse all the stones you’ve cleaned. Vinegar might disrupt the pH of the water, possibly creating chaos inside the tank.

Also, if you notice fizzing or foaming on the rock you’ve attempted to clean, stop and rinse the stone immediately. This is an indication that the rock has high calcium carbonate content, and vinegar might ruin it. 

If this happens, consider taking the rocks out of the tank altogether. Calcium carbonate can also affect the pH without you noticing, which will ruin the water quality.

If, for any reason, using vinegar is not the right choice for your situation, don’t despair. There are many other methods that are just as effective. As long as you keep your rocks clean, your fish will thrive – no matter the method you choose.