Algex 45-90 is used to treat the biological growths of both fuels and lubricants. These growths become apparent when continual filter blockage occurs, or cutting fluids become malodorous. The treatment rate is 1:2500, one litre Algex 45-90 per 2500 litres of fuel or fluid.
A good way to test fuel is to take a 200 ml. sample from the fuel filter, put it in a clear 500 ml. bottle, add 200 mls. of clean water. Most biological growths will remain in the fuel layer, or on the interphase between the fuel and water.