Can You Put Seashells In A Fish Tank – How To Do It Safely

Many devoted fishkeepers work hard to decorate their fish tanks as nicely as they can. Seashells are among the most eye-catching ornaments that people like to put inside aquariums.

But the most important query is, “Can You Put Seashells In A Fish Tank?” In this article, I’ll discuss if you may put seashells in your aquarium and, if so, how to do it properly to prevent harming your fish.”

Seashells As Aquarium Decor: An Overview

seashells and decorations

Shells play a significant role in both human culture and the ecological and geological processes that occur at beaches. The calcium carbonate-based hard exoskeleton of invertebrates that is readily found on beaches is known as a seashell.

In terms of culture, people have gathered shells for millennia for several purposes. As a result, the fish caretakers have developed a serious interest in seashells.

It makes sense to want to decorate your fish tanks with shells as the fish tank is a miniature representation of the ocean and sea. But even in a more broad sense, having shells provides an aquarium with a striking appearance.

Is It OK To Put Seashells In A Fish Tank?

Seashells may be generally benign, however, they do contain the acidifying substance calcite. Here are a few helpful guides we’ve provided for your reference.

Changes in Water’s PH

Calcium carbonate, a base that lowers pH, is frequently produced by seashells, and its production occurs nearly concurrently with the elimination of sodium carbonate, another compound that has probabilistic effects on pH levels.

So if you started dissolving shells, you would see an increase in sodium ion activity in the surrounding fluids and a corresponding rise in the rate of limestone breakdown (OH-).

Growth of Bacteria

Fish waste and debris are key factors contributing to the growth of bacteria in tank water.

These bio-loads are frequently trapped inside the shells. The leathery, flaky layer that most seashells have is called the periostracum.

The shell’s ridges, nooks, and crevices can all harbor bacteria, algae, and other organisms. The filtering system cannot effectively control them as a result.

Pest and Organism Presence

You must keep in mind that once at a time, a creature called seashells home. Therefore, even after it has died, there may still be remnants of it inside the shells.

Furthermore, the conveniently accessible beach shells may contain a variety of unwelcome microorganisms, such as parasites and pests.

Without adequate sanitization, these organisms might migrate into your aquarium and possibly endanger your fish if you place the shells within the tank.

How To Put Seashells In A Fish Tank Safely?

Make sure the seashells are completely cleaned before adding them to your fish aquarium. These actions may be helpful:

  • Any organic things, such as sticky seaweed remnants, should be removed.
  • To eliminate salt and chlorides, if necessary, brush off any leftover debris and thoroughly rinse in freshwater.
  • Before moving on to the following phase, the shells should be moist, not dry or wet.
  • With a dull knife or spoon handle, scrape off unnecessary components like spines before giving the animal another thorough wash in plenty of fresh water.
  • Using soap and a brush to clean the painted surface, rinse the shell in fresh water.
  • Before utilizing shells for an aquarium, make sure all critters have been taken out of the apertures. You may do this by pouring some flowing water through some of the openings.

What Are The Advantages Of Putting Seashells In Your Tank?

You now understand how to securely add seashells to your aquarium. Let me list the many benefits of adding seashells to the tank.

reef tank

Tank Decoration

Seashells look quite nice in the fish tank. Even those who are unfamiliar with fish or fish keeping take a second glance at a tank that contains shells.

Additionally, the seashells relate the tank’s surroundings to that of an ocean or pond. If you combine some aquatic plants with shells, you may create an excellent environment for your fish.

Balancing Calcium Requirement

Calcium is almost usually linked to bone development in general. Fish also require a healthy calcium intake for the development of their bones.

There are many different types of minerals present, particularly in saltwater aquariums, although the quantities of calcium are minimal. As a result, the calcium levels need to be monitored and balanced by the fishkeepers.

In contrast, the fish keeper in a freshwater aquarium does not need to add any calcium because it would endanger the fish more than it would benefit them. Calcium will interfere with the pH levels of the tank water.

Hiding Space For Little Fish

Diverse species of fish are popular among fish keepers to maintain in their aquariums. Fish of all types, sizes, and shapes are kept together.

Little fish are frequently hurt or bullied by larger fish, and even newcomers run a significant danger of being eaten by their parents or other fish.

Fishkeepers typically give the fish artificial caves as hiding places as a preventative measure. Similar to this, seashells serve as excellent examples of places where little fish may hide from larger ones.

Where Can You Find Seashells Easily?


You may gather seashells from the shore whenever you get the chance to visit a beach. The best part about collecting seashells is that all you need is a keen eye and a sense of curiosity.

You may bring a shovel, a bag made of fine mesh, a net, water shoes, and polarized eyewear.

Arrive early in the day. The advantages of dawn shelling are numerous if you can wake up early enough. The sun doesn’t get too hot, the tides are often low, and there are no visitors on the beaches.

Online stores

seashells online stores

If you don’t have time to visit the beaches, you may always locate the closest aquarium stores to buy seashells. These days, you may buy seashells from a variety of internet retailers.

These shops sell seashells in a variety of varieties, sizes, and forms. Furthermore, there are no unwelcome occupants inside the shell itself.


Can You Put Anything To Decorate Your Fish Tank?

You need to be extremely careful while selecting the decorations for your aquarium. A glass tank used for an aquarium is a miniature universe. The tank’s inhabitants can live and thrive because of its unique habitat and circumstances.

You should refrain from placing the following items inside your tank:

  • Plastic ornaments
  • Metal decorations
  • Beach sand
  • Wood décor

How Do You Clean Aquarium Shells From The Beach?

Avoid washing the seashells with tap water once you’ve collected them from the beach. The natural adhesive that holds the shell together will be destroyed and won’t regrow.

To get rid of dirt in tight spaces, some advise using a toothbrush and dish soap to gently clean shells.

To get rid of any lingering germs or fungus from your walk down the beach, boil the shell for 10 minutes. Before using in an aquarium tank, thoroughly rinse.

Others advise putting them in a bucket, half-filling it with cold room temperature water, and adding around 2 teaspoons of salt per gallon of water (the suggested ratio is 1 tsp/gallon).

If you’d want to assist remove sand, you may also add some vinegar or lemon juice.

Can Seashells Be Used In Freshwater Aquariums?

Despite what you may have observed in their natural habitat, seashells are not appropriate for freshwater aquariums. Numerous forms of algae thrive in calcium-rich water and will feed on the shells, while seashells will leach calcium into the water.

These kinds of aquatic life might cause your tank to collapse or overpopulate with undesired species while it is cycling.

How Do We Maintain The Seashells In Good Condition?

The colors of seashells will eventually get distorted, therefore it’s crucial to know how to maintain them.

Mineral oil may be put onto a brush and then applied all over the shell. Alternatively, you might gently apply the mineral oil onto the shell with your finger.

The shell will be preserved while getting a sheen from mineral oil. For around 24 hours, leave the shells on a thin towel (not a heavy one that would absorb part of the oil). This will allow the oil to solidify.


Natural treasures like seashells are more valuable to culture and fish keepers. Your tank’s aesthetic appeal is increased by adding seashells.

For the same reason, a lot of people maintain seashells in their aquariums. Hence, you may add seashells to your tank, but you must be knowledgeable about the state of your tank and how to care for it.