To measure well is to know truly!

Water quality

Good water quality is crucial if you want to successfully keep koi. Keeping koi is easy, but maintaining good water quality is the challenge! Now, don't panic; it's not rocket science, as long as you follow a few important basic rules.

To measure

Pond owners are naturally inclined to claim that they can determine whether the water quality is good based on the clarity of the water or the behavior of the inhabitants. This isn't an illogical notion, but nothing could be further from the truth. Water clarity says nothing about its quality, and fish behavior can be normal one day, while the next, all hell breaks loose because, for example, the pH (acidity) has plummeted (pH crash). To prevent this misery, it's important to regularly measure key parameters such as ammonia, nitrite, nitrate, pH, and KH. Add the GH (high-temperature nitrogen) to this if you have a heavily planted pond. This ensures the right conditions for your fish and allows you to spot problems from a mile away.

Tips

Beginning hobbyists, in particular, will initially perform water parameters using so-called drip tests. There's nothing wrong with this per se, and it's more than sufficient for our purposes. However, errors are often made during measurement, and the results can lead you astray. Here are some tips to minimize this risk:

• Read the instructions carefully and make sure the test kit has not expired.
• Store the test kit in a cool, dark place, but not in the refrigerator.
• Make sure your materials (curvettes/test tubes, pipettes, etc.) are clean. Clean your materials immediately after use.
• Fill the curvette with the correct amount of pond water (this can vary between parameters within a test set).
• Add the correct number of drops in the correct order to the curvette. The number of drops also often varies by parameter. Hold the bottle upside down at 180 degrees (not tilted) to achieve the correct droplet size. Gently shake the curvette between each addition to ensure thorough mixing.
• Wait until the time specified in the instructions has elapsed before reading the correct color of the reagent.
• Also test your tap water and compare it with the specifications from your water supplier. This will give you an indication of any deviation from the test kit and also allow you to test whether the test kit is still working properly.

How often should I measure?

For new ponds just starting up or for major changes in fish stock or filtering, I would recommend testing daily or every other day and adjusting as needed. For minor changes to the pond or seasonal changes, I would test weekly. For stable ponds running for more than two years, monthly testing is probably sufficient.

Author: Joop van Tol (Koitoday)