Aluminium reacts with Eriochrome Cyanine R indicator in slightly acid solution to produce a pink-red coloured complex.

• Test is carried out by adding one of each tablet to a sample of the water
• The first tablet acidifies the sample to bring any colloidal aluminium into solution
• The second tablet buffers the solution to provide the correct conditions for the test

The presence of ascorbic acid eliminates interference from iron and manganese.

In the Palintest aluminium method the necessary reagents are incorporated into two test tablets.

The intensity of the colour produced in the test is proportional to the aluminium concentration and is measured using a Palintest Photometer.