How to Cure Concrete for Koi Ponds

Koi ponds are a beautiful addition to a home. Koi are elegant and low-maintenance fish that can live for many years. To properly care for koi, a concrete fish pond can be your best option. Concrete is easy to clean and maintain, and it makes a good habitat for the fish. However, a concrete pond needs to be cured before you can put your koi fish into it. Otherwise, it can cause your fish to become ill or die. Curing concrete is a relatively simple process that can be completed in about three days. Once the concrete is cured, your fish can safely be housed in a concrete pond.

Things You'll Need

  • Wooden slats
  • Hammer
  • Nails
  • Plastic sheeting
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Instructions

    • 1

      Place wooden slats around the perimeter of your koi pond. They will act as a barrier. The concrete needs to be completely submerged in water to cure.

    • 2

      Hammer the wooden slats in place around the edge of your pond if possible. Weigh them down with rocks or bricks if they cannot be nailed in place.

    • 3

      Attach plastic sheeting to the wooden slats to form an airtight surface. Attach the plastic sheets so that they cover the area where the wood sits against the ground to prevent water from seeping out.

    • 4

      Fill your koi pond with water, up to the level of the barrier you created. To cure properly, concrete needs to be kept at 100 percent humidity.

    • 5

      Leave the concrete submerged for three to seven days. Although a seven-day period will give you the most effective curing of the concrete, a three-day period will also suffice.

    • 6

      Drain the koi pond after three to seven days and replace the water with fresh, clean water, or begin running a filtering system to remove any impurities left by the cured concrete before adding your koi to the pond.