How To Acclimate Your New Koi Fish 

Koi fish, members of the carp family (Cyprinus carpio), are renowned for their tranquil beauty and vibrant colours.

These elegant creatures have become beloved additions to ponds around the world, bringing serenity and aesthetic delight to their owners.

However, when introducing new Koi to your pond, it’s crucial to acclimate them correctly. Failing to do so can jeopardize their well-being and even lead to fatalities.

How to Properly Acclimate Your New Koi Fish

Koi fish are quite adaptable to a range of water temperatures, with their ideal range being between 18 to 30 degrees Celsius. Nevertheless, abrupt temperature changes can be disastrous for them. Therefore, the key is to make their transition into their new environment as stress-free as possible.

Here are the essential steps to follow when receiving and introducing new Koi fish to your pond:

Step 1: Visual Inspection

Begin by unpacking your Koi from the carton box in a softly lit room. Inspect them through the sides of the plastic bag, keeping a keen eye out for any significant signs of distress. It’s crucial to avoid exposing the fish to direct sunlight immediately, as this could startle them and induce stress. Signs of stress may include:

  • Frequent sideways swimming or swimming in one direction.
  • Jumping out of the water.
  • Scratching or scraping against the pond wall.
  • Sluggishness or lying idle at the bottom of the shipping container.
  • Swimming with their heads down.
  • Erratic swimming patterns.
  • Frequent gasping for air.
  • Isolation from other Koi fish.

If you don’t notice any unusual behaviour, proceed to the next step.

Step 2: Equalize Water Temperature by Floating the Bag

Always measure the water temperature inside the fish bag and compare it to the temperature of your Koi fish pond. Depending on the temperature difference, you should float the bag on the surface of the pond.

This process typically takes between 15 to 30 minutes. During this period, stay vigilant and closely monitor the fish.

It’s important to note that transitioning Koi fish from warm to cold water is more stressful than the reverse. Therefore, acclimating them from warm to cold should be done slowly and without causing undue stress to the fish. Ideally, perform this acclimation process during the early morning hours for the best results.

How To Acclimate Your New Koi Fish

Step 3: Introduce the Koi Fish to the Pond

With utmost care, scoop the fish out of the plastic bag, preferably using your bare hands. Your hands are less abrasive than other tools, which helps protect the Koi fish’s delicate slime coating.

If the fish is too large for you to handle, use a net or simply allow the fish to swim from the bag into the pond.

Important note: Do not add the shipping water from the bag into your pond.

For more information on creating garden water features and Koi fish ponds, you can explore the links below.