Can You Put Seashells In A Fish Tank? Any Adverse Effects?

Every passionate fishkeeper like myself desires to make our fish tank as eye-catching as possible. There is a big pride factor when it comes to making fish tanks attractive. So, what can we do to make our tanks more eye-catching and attractive? We add tank decors, right? Talking about decors, Seashells are one of the most eye-catching decors people like to put inside the tank. But the big question is, “Can You Put Seashells In A Fish Tank?”

Yes, you can put seashells in your tank but only after the completion of a proper sanitization and cleaning process. Especially if you have a freshwater fish tank, then it is strictly recommended to either avoid them or clean them with full devotion.

In this article, I will be shedding light on whether you can put seashells in your aquarium, and if yes, then how you can do it properly. Furthermore, I will also include some extra knowledge relating to the topic for your convenience.

Seashells As Aquarium Decor: An Overview

Seashells are the hard protective exoskeleton of the invertebrates made of calcium carbonate found freely on the beaches. Since ancient times, humans have used seashells for various purposes like tools, jewelry, and even decorations.

Culturally, the shells are symbols of water and the ocean. Hence it reminds most people of the open sea and ocean. Due to this, the seashells have become quite the object of fascination for the fish keepers.

As the fish tank is a small embodiment of the ocean and sea, wanting to put the shells in your fish tanks for decors is quite understandable. But, even in a general sense, having shells surely gives an aquarium eye-catching vibes.

Are Seashells Safe to Put In A Fish Tank?

Well, having a tank decorated with seashells is quite a fun idea, but the reality is a little different. Seashells actually can be quite harmful to your tank environment and its inhabitants if you are not careful. Let us talk about why putting seashells inside the aquarium is not so safe for the fish, Shall we?

The following are the reasons why it is not safe to put seashells in a fish tank:

Change In Water PH Levels

If you want to increase the water ph levels in your tank, then seashells do the job well. But,  you will have to commit yourself to analyzing your tank ph levels carefully.

Seashells contain calcium; hence they cause a chemical imbalance in the water, causing harm. In my personal opinion, anything that causes a chemical imbalance in the tank water should be avoided.

In the case of your inability to keep the ph levels in check, outcomes can be very harmful to your fish. To be more specific, high pH levels harm the fish by denaturing their cellular membranes. So learn How to Adjust pH in Fish Tank from here.

You can also add up a water test kit to your list. This will help you to check the water regularly and maintain a balance in the same manner. API FRESHWATER MASTER TEST KIT 800-Test Freshwater Aquarium Water Master Test Kit, White, Single is one of the best I have used so far.

Increment Of Bacteria

One of the main causes of bacterial increment in the tank water is debris and fish waste. Lots of these bio-loads get trapped inside the shells. Due to this, they are not properly managed by the filtration system.

Hence, the fish waste and other debris that get trapped inside the shells are the perfect breeding space for bacterias. Furthermore, fish are quite prone to some of the types of bacterias, which can prove fatal.

Presence Of Pest And Organism

You have to remember, seashells were the home of a creature once. So, even after its demise, pieces of it can still be prevalent inside the shells. Furthermore, various kinds of unwanted microorganisms like parasites and pests can be living in the shells that you find easily at the beach.

If you put the shells inside the tank without proper sanitization, these creatures can migrate into your aquarium and even prove fatal for your fish. Especially in freshwater tanks, as there is no salt in the water, the pest and bacteria can safely multiply.

How To Put Seashells In A Fish Tank Safely?

So, recently in the upper segments, we talked about the harmful and risky outcomes you can face when you put the seashells in your tank. Well, the good news is a way through which you can put them in aquariums, but I recommend that you check the pH levels from time to time.

Follow the following steps to make seashells safe to put inside the tank:

  • Heat the pan with water to the boiling point
  • Submerge the shells in the water for 8 to 10 minutes
  • Once cooled, remove the shells and empty the debris.
  • Scrub the shells thoroughly until you are satisfied
  • Repeat the process just to be on the safe side.

Now, for those of you who do not think they can invest time in carefully analyzing the pH and alkalinity levels, then I suggest you keep some harmless artificial seashells.

I suggest PH PandaHall Small Seashells, 1400-1500Pcs 7-12mm Tiny Natural Sea Shell Ocean Spiral Seashells Undyed No Hole Miniature Shells for Resin Candle Home Party Wedding Decor Fish Tank Vase Filler.

What Are The Advantages Of Putting Seashells In Your Tank?

Now, you know how you can put seashells safely in your tank. Let me tell you the various advantages of putting seashells inside the tank.

Tank Decoration

Let us be honest seashells make the fish tank look very attractive. Even the people who do not know much about the fish or fish keeping look twice at a tank with shells.

Furthermore, I personally believe the seashells somehow connect the environment of the tank to that of the ocean or a pond. Add some aquatic plants along with the shells, and you got yourself a wonderful tank for your fish.

Balancing Calcium Requirement

In general, calcium is always associated with the growth of bones. Similarly, fish also need a balanced level of calcium for the growth of their bones. Especially, in saltwater aquariums, there are various types of minerals present but the levels of calcium are low. Due to this, the fishkeepers need to supervise and balance the calcium levels.

Whereas, in the freshwater aquarium, the fish keeper does not need to add any calcium as it can do more harm to the fish than good. As mentioned in the upper segments, calcium will mess with the pH levels of the tank water.

You might also like Why Is Calcium Important For Your Shrimps?

Hiding Space For Little Fish

Fish keepers like to keep different types of fish in their tanks. Fish with different natures, shapes, and sizes are kept together. Often, some big fish tend to harm or bully the little ones; even the new fray has a high risk of being eaten by their parents or other fish.

So, as prevention, fishkeepers tend to provide the fish with hiding spots in the form of artificial caves. Similarly, seashells prove to be great examples of hiding space for small fish from the big ones.

Where Can You Find Seashells Easily?

There are various places you can find seashells. If you are thinking of putting seashells in your tank, here is how you can find them.


The most obvious answer is the seashores and beaches. You can get seashells in all sorts of shapes and sizes if you search for them. If you have a desired shape of shell you want to pick, then it may be a hard finding.

Moreover, I again recommend you to properly check the seashells first hand for any resident creature inhabiting them. Afterward, follow the cleaning process I mentioned above to protect your tank from any hazards.

Online stores

Nowadays, you will find different online stores that sell seashells. These stores are different ranges, shapes, sizes of seashells. Furthermore, you do not have to worry about any unwanted residents in the shell itself.

Amazon is your go-to oasis to find any kind of product and seashells are no exception. Otherwise, online stores and companies like the Seashell Company, ShellWala, and Buy the sea are some of the popular stores to get the shells.

I would suggest the following products:

Frequently Asked Questions

Can You Put Anything To Decorate Your Fish Tank?

No, you should be very careful upon choosing the decors for decorating your tank. An aquarium tank is a small world limited inside a glass container. It has its own environment and conditions for the tank residents to survive and thrive.

Due to this, you have to be careful not to harm the tank environment in any condition by placing non-compatible decors in your tank. So, I recommend you not to put anything inside your tank that changes its chemistry in any way or things that can physically harm the fish.

The following are some of the things you should avoid putting inside your tank:

  • Plastic decors
  • Wood
  • Beach sand
  • Seashells
  • Metal decors

For more such information, you can check Aquarium Decorations: What To and What Not To Add – Beginners Guide.

Do Seashells Dissolve in Water?

Yes, seashells can dissolve in the water due to the high acidity of the tank water itself. For normal cases, it will take a long time for the shells to dissolve. So, you do not have to worry about the sudden disappearance of the shells!!

Humor aside, your seashells can dissolve faster if somehow the acidity of your tank water has increased.


It is a fact that placing seashells inside your tank enhances its beauty and attractiveness. Due to this, many people keep seashells in their aquarium for the same reason. But, seashells can cause harm to the tank environment and the fish if the fishkeeper is too careless in handling the situation.

Different types of bacteria and microorganisms can inhabit the shells. Fishkeepers with freshwater tanks need to be extra careful as the seashells can easily increase the pH levels and water chemistry of the tank water.

In general, you can put seashells in your tank, but you have to commit yourself to follow the above cleaning method and properly supervising the water chemistry of your tank. If you are not ready to commit yourself, then I recommend you to not put the seashells in your tank.

If you have any further queries, then feel free to comment in the comment box below.

Related articles: