Can You Put Concrete in Aquarium?

Can You Put Concrete in Aquarium?

Typically, concrete in an aquarium balances ecology, hosts numerous microorganisms, and adds appeal with a moderately expensive method. Also, non-toxic concrete allows more creativity in a rock formation, and the procedure costs you around $26 to $35 with the molding kit price. 

Can You Put Concrete in Aquarium? You can put concrete in an aquarium by selecting high-quality concrete, cure it for around 8 to 12 days with water soaking, stabilize the pH and bring it on the mold table. Furthermore, adjust it with the side walls at the tank bottom and allow bacterial growth to attract microorganisms.

Generally, you can add it with several curing and soaking techniques, because several fish tank microorganism grows on them. Also, they have an attractive appearance, which results in playful activities, active fish swimming, and more oxygenation. 

Furthermore, the aquarium water becomes alive, supports fish life, and keeps them healthy for their standard life limits.

Can you put concrete directly in an aquarium?

Generally, directly putting concrete in your living fish tank is not safe. Furthermore, avoiding the instructions lead to a sudden drop in the water pH that is not beneficial for healthy fish life. 

Also, the living creatures die, and microorganism vanishes from the ecosystem. 

Also, never add a tiny particle of concrete without appropriate control methods because the results are irreversible. In addition, it shortens the fish’s lifespan, and the creature dies without any apparent sign.

How to put concrete in an aquarium?

For an aquarium, concrete rocks are beneficial than raw material because they enhance the natural appearance. Also, for making concrete rocks, I have mentioned a step-wise procedure below. 

Purchase and gather concrete rocks ingredients

Typically, commercial aquarium concrete is not expensive, and they have few drawbacks due to inappropriate handling. But, you can make them with a few skills and expert guidelines. 

However, selecting good quality and supportive products is a challenging procedure. Also, overall formation depends on its structure and design. 

Also, for the evaporation of moisture from its surface, use the curing technique. Furthermore, hose down the material in the water around 8 to 12 times daily for at least 8 to 10 days. 

Moreover, it is a curing procedure that results in moisture removal and makes it suitable for aquariums. 

However, purchase the already cured concrete or a mixture of cement with water. In addition, buy ready-made items from authentic stores, and the costs vary according to the processing and applied methods. 

For the development of natural-looking habitats, use seashells, charcoal, sea salt, and coral sand. 

As a result, the rocks become natural, appealing, and smooth in texture.

Mix the components 

Typically, with a commercial mixture of cement, concrete, and rocks, the procedure is convenient. But, with self-cured concrete, follow these instructions and make them attractive. Next, take 2 to 3 parts of the concrete and mix it with one section of cement in a bucket.

Furthermore, add water, mix it and turn it into a paste-like consistency. Also, before molding the mixture, add the sea salt because you cannot add it after the mixture turns into other shapes.

Also, avoid salts during wet conditions because sea salt can dissolve the cement, and prices become challenging. 

Next, add 34 to 36 grams of sea salt in 1 to 2 liters of water. Then, put the concrete and cement mixture in that water bucket, leave it for around 4 to 5 minutes. Now, take it out, remove water and utilize the material for a rock formation.

To get a natural, gritty, and rock appearance, roll the material in the sand. Furthermore, add the colorful ground seashells and coral to the mixture. Now, change them into required shapes, and use molds for appropriate shape adjustment.

Also, keep the size according to the internal environment, decorative items, and size of your aquarium. Moreover, it should not accommodate more than 12% to 13% of the tank volume.

Cure the cement and delicate rocks for the aquarium

Typically, the new, molded rocks are yet delicate and require appropriate time for drying. In these situations, follow the rock curing technique, put them on a stable surface, and leave for drying conditions.

Now, remove the excess material from these items, and put them in fresh water for around 3 to 5 minutes. Furthermore, leave them for soaking and check wager pH regularly for 5 to 7 days. 

However, the standard pH for these procedures is around 7 to 7.5 approximately. In addition, when you attain this pH, it indicates that there is no excessive sea salt, and the concrete is ready for the fish tank adjustments.

Carry out appropriate seeding and adjustment

To achieve maximum living benefits, introduce the rocks in an ecosystem. Also, allow bacterial growth on the new concrete and the procedure requires time and patience equally. 

Furthermore, once the bacteria start their growth, and they alter the artificial rocks into living ones. 

Also, the healthy habitat and abundance of microorganisms support the rocks because they are attracted to these items. Many people also add legos to the aquarium.

However, adjustments depend on the owner, but people prefer them in corners nears the tank walls. Also, the shapes, sizes, and colors vary with various ideas and different techniques.

Pros and cons to adding concrete in an aquarium



As rocks, the concrete immediately increases the tank appeal with attractive colors and variable shapes. The direct drop of a concrete piece drops the pH level drastically, and fish dies.
It keeps the water cool in high temperatures and increases fish survival in these conditions. The water dissolving paints on concrete rocks results in leaking, and fish eat these harmful chemicals. All of it results in life-threatening diseases and a shorter lifespan.
They help in biological filtration and provide a home for beneficial bacteria. The poor-quality commercial mixture lacks appropriate curing procedures and destroys the natural tank environment.
It work as decorative items, and once developed into living rocks, they support plant growth. The presence of lime in the ready-made material increases the water harness and increases the alkalinity and acidity beyond the standard limits.

Is concrete safe for an aquarium?

Generally, concrete is safe but requires several modifications of long times for appropriate adjustment. 

Furthermore, after their inappropriate addition, the calcium hardness increases, and it stresses the tank fish and eventually kills them. 

Moreover, supporting techniques are available to make it safe, which facilitates the life of tiny creatures, and they swim in a healthy environment. 

Which concrete should you avoid in an aquarium and why?

Typically, the commercial concrete mixture comes with different indications and warning on its label. 

Also, few of them have a statement of polymer-modified or only polymer. Avoid these mixtures for the fish tanks because it has pH differences and does not support any small to a medium aquarium.

Also, it requires 1 to 2 months curing under strict circumstances and stability of pH at the standard level. Furthermore, the ready-made concrete cement mixtures with limestone and marbles are not desirable and safe for a fish tank.

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