Palintest PM166 Aluminum Reagent Tablets 50 per box. Aluminium reacts with Eriochrome Cyanine R indicator in slightly acid solution to produce a pink-red coloured complex. 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 test is simply 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 and the second tablet buffers the solution to provide the correct conditions for the test.