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Testing your aquarium water

Aquariums offer a fantastic home for fish and can become a huge part of your life as either a casual fish keeper, or a full-blown hobbyist. However, aquariums offer some unique challenges and unknown abnormalities that can throw the balance off and cause health issues for your aquatic life.

Processes such as the Nitrogren Cycle will affect your fish and their environment. The balance of chemicals in your water will be constantly changing, and because they are invisible, you won’t know what is going on.

The only way you will ever know something is wrong is if you test your water regularly and keep a record of previous results to identify changes (or your fish get sick!).

Two of the primary causes of these chemical fluctuations are; overstocking (keeping too many fish), as well as waste build-up/pollutants (typically over-feeding or dead, rotting livestock or plants).

Our testing kits allow you to test the water for Ammonia, Nitrite, Nitrate, water hardness (dip test only) and pH. See our how-to-use videos below for our Complete Aquarium Dip Test Kit.

Using the Complete Dip Test Kit:

It is handy to keep a diary record of your test results to refer to, or compare, when completing maintenance or future tests.

Any unsafe results will need to be treated to prevent health issues for your fish.

See the videos above for more detailed information on dealing with each specific issue or use our diagnostic tool for further advice.


How accurate are aquarium test kits?

Aquarium test kits are an invaluable tool for any aquarium keeper to ensure their water is healthy and safe for their fish. Testing your aquarium can indicate potential issues before they become a problem. However, the accuracy of the results is dependent on the quality of the test kit used.

How often should I test my aquarium water?

Testing should be done at least every 2- 3 days or monthly if the values remain stable throughout that period. Beginners to aquarium keeping need to test important parameters of water, such as KH, pH, NH3/NH4 and NO2 /NO3. Once a routine is established, these parameters should be tested more regularly.

How do you know if your aquarium water quality is poor?

Poor water quality in an aquarium can have detrimental effects on the health and well-being of the fish and other inhabitants. Here are some signs that indicate your aquarium water quality may be poor:

  • Cloudy or discoloured water: If the water in your aquarium appears cloudy, murky, or has a noticeable coloration (e.g., green, brown), it may indicate an imbalance in the water chemistry or the presence of algae or suspended particles.
  • Smell: A strong and unpleasant smell coming from the aquarium water can be a sign of poor water quality. It could indicate the presence of excess organic waste, decaying matter, or an imbalance in the bacterial ecosystem.
  • Algae growth: Excessive algae growth on the surfaces of the tank, including the glass, substrate, or decorations, can suggest poor water quality. Algae thrive in environments with excess nutrients, which can be a result of inadequate maintenance or imbalanced nutrient levels.
  • Sick or stressed fish: Poor water quality can cause stress and health problems in fish. Watch for signs of fish distress, such as lethargy, loss of appetite, gasping at the water surface, fin rot, fungus, or other visible signs of illness. These symptoms can be an indication of ammonia, nitrite, or nitrate toxicity.
  • Altered pH levels: Rapid or significant changes in the pH levels of the aquarium water can indicate poor water quality. Fish prefer stable pH levels, so any drastic fluctuations can stress them and affect their health.
  • High ammonia, nitrite, or nitrate levels: High levels of ammonia, nitrite, or nitrate can be toxic to fish and other aquatic organisms.

How can I test my aquarium water without a kit?

You can get your fish tank water tested for free by simply taking a sample to your local fish store. Most aquarium stores are more than willing to provide this service for you.

Another way to test fish tank water without a kit is to do a visual observation. Look for signs of distress in the fish or any noticeable changes in water colour or clarity. If you see any of these indicators, then it is likely that there is an issue with your aquarium water quality.

We generally recommend using a test kit for accurate results. This will give you the best indication of the water quality in your aquarium and allow you to make any necessary changes accordingly.

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