Is A Concrete Pond Safe for Fish?

Concrete is ideal for koi ponds since it allows you to create whatever form you wish. This long-lasting substance will survive for decades, which is crucial given that so many koi live around 25 – 35 years.

Enormous ponds that can handle these large fish may also be built using concrete. Before adding koi, the pond’s concrete must be cured for several weeks to remove excess lime that might dangerously elevate the water’s alkalinity.

Fish ponds may be built using cement, but they must be cured and cleaned before the pond can be filled with fish. It may disrupt the pH balance in the first several weeks of contact with water, making it difficult to maintain a fish-friendly ph.

Rather than filling and using the pond immediately after draining it, wait two weeks and repeat the process. This should take approximately a month and will result in a cement-lined pond that is safe for your fish.

Is A Concrete Pond Safe for Fish?

Without any extra coatings, concrete ponds may be “cured” and kept fish-safe. The freshly created pond should be filled with water for at least a week before draining and refilling. Drain and replenish again after two weeks. Drain and re-fill after three weeks.

Concrete fish tanks may be built below or above ground. Concrete ponds are particularly common in cities where fishing is popular. Without the use of special coatings, concrete ponds may be “cured” and made fish-safe. Fill the freshly created fish pond for a week before draining and refilling. Drain and refill after 2 weeks, then drain and refill after 3 weeks. Wait another week before draining and refilling for the fourth time.

What Are the Disadvantages of Earthen Pond?

Ground fish ponds may be good if you have large enough land to use. But earthen pools come with several drawbacks, including:

Ammonia Buildup:

The pace at which ammonia levels in this pond are is worrying. It is difficult to identify, as it would be in concrete ponds. The water is not clean by itself, but when fish excrement is added, it becomes more concentrated, potentially resulting in the loss of a significant number of fish.


Floods will make fish out of the pond and can disappear without a trace.

What Kind of Concrete Should I Use for A Fish Pond?

A mix design of 3000 psi is feasible to implement if you live in an area where the ground does not freeze during the winter months. You might save time by using ready-mixed concrete, but 5000-psi cement is available in sacks at Home Depot. My recommendation is that you use 3/8-inch rebar (also known as #3 bar) to strengthen your new pond.

Does A Concrete Pond Need to Be Sealed?

Concrete, on the other hand, is a porous material that, if not sealed with a waterproofing agent, would ultimately drain lime and other pollutants into your pond. There are a variety of solutions available on the market that may be used to cover your concrete pond with a waterproof, rubber-like coating.


Making a concrete pond is very useful. They can be used for a long time. However, concrete ponds require high costs to make happen. There is no definite benchmark regarding the price of making a concrete pond. If it is too expensive, you can use cement or earthen pond.