eSHa Aqua Quick Test. Good water quality is essential for the fish and plants in your aquarium. Regular testing of water quality values helps ensure fish live healthy, happy and long lives. With the eSHa Aqua Quick Test you can monitor five values which are crucial for good water quality: pH (acidity), KH (carbonate hardness), GH (general hardness), NO2 (nitrite) NO3 (nitrate). These values determine how healthy your aquarium is. Abnormal values can cause problems such as disease, algae blooms, abnormal growth and reproduction. Water quality is the result of many factors such as : plants, fish, aquarium volume etc. as well as external factors such as overfeeding, type of water added, the filter used and duration and amount of lighting etc. Regular use of eSHa Aqua Quick Test allows you to spot water quality problems in time to take corrective action. Simply dip the test strip in your aquarium or pond and compare the colours on the strip with the colour chart on the container.