The use of sea water in the flotation of Cu-Mo sulfide ores requires better understanding of the effect of electrolyte concentration on performance of flocculants used in the solid/liquid separation unit operations. This paper deals with optimisation of the experimental procedure that will be used in studying the effect of sea water on flocculation. In the tests reported in this paper the tailings from one of Chile major flotation plants were subjected to the flocculation tests with Orifloc-2010 polyacrylamide in a Couette type reactor. It was shown that the flocculation efficiency can be dramatically improved by optimising the shear rate in the reactor, and that the procedure based on the ultra-flocculation can be used as a standardized experimental procedure in testing flocculants.