Only one side of the test is designed to react to high pH in the fuel. This is rarely seen. Elevated pH indicates water contamination, microbial activity, or both, which affect the overall tank condition.

This test has identified microbial growth by the appearance of a black spot on the paddle, confirming active contamination. The blue color shift further indicates high pH in the tank.

The age of the fuel will influence the test values, and the sampling location is critical. Do not take samples from the fuel filter. Filter housings collect debris and will give a false indication of the fuel’s true condition.

For an accurate assessment, take one sample from the bottom of the tank and another from the mid-tank level. This provides a much clearer representation of the actual fuel condition.

To correct the issue, filter the fuel down to 2 microns and retest. Removing the water and solids should produce a noticeable change in the test results.

After retesting, if the pH remains elevated, adding a biocide is appropriate. After treatment, re-filter and retest.

Abnormal Fuel Test Results?

Use Dieselcraft fuel polishing systems and Micro Test DS-1 kits to diagnose contamination and restore stored diesel fuel.

Call 530-613-2150
Auburn, California USA
Made in the USA