Test Kits
Drop tests and strips for pH, KH, GH, nitrite, nitrate, phosphate, potassium, iron and CO2, plus refills and test cases.
How to choose?
Advice and care
How to choose an aquarium water test
Choose the test by what you want to know: cycling, routine care or plant nutrition.
New tank
Ammonium and nitrite show when the filter has cycled.
Planted tank
Phosphate, potassium, iron and CO2 show whether plants have enough nutrients.
Drops or strips
Drop tests are more accurate, strips quicker for an overview.
Popular brands
All brandsFrequently asked questions
Which values should I measure?
For routine care pH, KH, GH and nitrate, plus ammonium and nitrite in a new tank. In a planted tank it also helps to test phosphate, potassium and iron.
What is a refill for?
A refill contains only the reagents, so you can keep using the test you have. It makes sense when you test the same value often.
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Many aquarium problems are present in the water long before fish or plants show them. Nitrite can rise after a filter clean, KH can drop and pH swing with it, and nitrate builds up slowly between water changes. Testing gives you the chance to act before fish fall ill.
With a drop test you add reagent to a water sample drop by drop and compare the colour with a chart; a test strip is dipped in the water and reads several values at once. A multi-test case suits beginners who do not yet know what their tap water contains.
Results are reliable when you read the colour in daylight against a white background, use clean test tubes and watch the reagents' shelf life. Test at the same time of day, because CO2 and pH change over the day, and note the readings to see the trend.
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