Wide Range pH Test Kit - 5.0-9.0

Product Description

Purpose And Benefits:
pH is the measure of acidity or alkalinity of water.

A pH reading of 7.0 is neutral, a reading above 7.0 is alkaline, and a reading lower than 7.0 is acidic.

Many factors can significantly alter the pH of pond water. Acid rain will lower the pH to 6.5 or less. If the carbonate hardness (KH) level is low the pH level will swing up and down over a 24-hour period.

Water with a high KH will usually have a high pH. Aquatic plants and algae remove carbon dioxide from the water during the day. This causes the pH to rise above pH 8.0 in the day then fall at night. These fluctuations are normal and will not harm pond life. Extremes in pH, however can stress fish and plants.

A pH of 7.0 is considered ideal for plants and fish. Many species of aquatic plants thrive at a slightly acid pH while koi and goldfish prefer a slightly alkaline pH. Therefore, an acceptable pH range is 6.8 to 7.6.


Q:When is the best time to check the pH?
A: The best time to check the pH is in the morning. As the sun comes up and the plants begin photosynthesis the pH will rise. If the water sample is taken during a sunny period the pH will always be high due to the temporary action of the plants. Therefore the best time to test pH is in the morning.

Q:My water garden has been set up for over two years and never had a pH problem. Now the pH test kit indicates a high pH problem. Why?
A: There are several possible reasons why pH can increase in an established pond.
Tap water may contain a substantial level of carbonate minerals (limestone). These carbonates can build up in some ponds and eventually cause the pH to increase. If your municipal water supply adds lime to the water to prevent pipe corrosion the pH may increase in the pond. If you have a well that is in a limestone deposit the pH will also rise over time. Making a partial water change once a month will dilute the carbonates and should help lower the pH. pH Down can also be added to lower the pH.

Product Code: 160 Tests

Price: NZ$19.95Inc. GST