The Colombo Quick Test 6 In 1 Test Strips provide a quick and simple way to check the 6 main water parameters in just over 1 minute. Suitable for both ponds and freshwater aquariums the Colombo Quick Test 6 In 1 Test Strips test for chlorine, acidity (pH), general hardness (GH), nitrite (NO2), nitrate (NO3) and carbonate hardness (KH)