My nitrate test indicates measurement results which I can’t read or which are far too low.
The reason is often an incorrect use of the test. It is important to shake the test vigorously for precisely one minute. All the other important steps can be read in the instructions.
The instructions point out that the comparator block should be used to compare the colours. Can this be done without the comparator block as well ? Or is there a factor from this comparison that is required for the measurement ?
The colour charts are intended to be used with the comparator block. In addition, when the comparator block is used with the blank water sample, this compensates the inherent water colour.
Therefore, if the comparator block is not used, there will most likely be deviations in the readings.
When doing the nitrate test, why can't I use 5 ml of water, one spoon of Reagent 1 and 3 drops of Reagent 2 ? Wouldn't that result in twice as many measurements ?
If you use 5 ml instead of the 10 ml of sample liquid, this would yield distorted results for two reasons.
For one, the powder for the reduction of NO₃ doesn't dissolve completely so that it forms a thin layer of sediment which causes difficulties when reading the results with too little water. Tapping the cuvette on the side several times helps by causing the powder to be deposited on the side.
Secondly, attention must be paid to the drop size of reagent 2, as the first drop from the drop dispenser can turn out to be smaller in individual cases, especially when the bottle is not held in a fully vertical position. This may also lead to incorrect measuring results. Therefore, it is advisable to use 10 ml in order to ensure accurate test results. Please make sure to really shake hard for exactly one minute in order for the colour to develop properly.
What is the shelf life of the JBL Nitrate Test haltbar ?
The JBL nitrate test has a shelf life of 2 years in the original sealed bottle.
The following is printed on the bottom of the packaging:
CH/B: 2262 (e.g.) = batch number
BBD: 05/12 (e.g.) = best-before date (month/year)
Please note that the best-before date does not apply for opened reagents. Exposure to atmospheric oxygen decreases the shelf life.
Do my water tests still work although they have been open for nine months?
Basically a sealed test keeps longer than an open one. How much the shelf life is reduced depends crucially on the handling and the storage conditions of the reagents. It may happen that a reagent in a test that has been open for 9 months doesn’t indicate correctly any more. However, additional information is needed to answer this question properly.