Description: -Aeromonas Selective Agar Base (Havelaar) is used for the detection of Aeromonas species in water and other liquid samples by membrane filter technique. This medium was formulated by Havelaar et al and also complies with the recommendations of USEPA Approved Method 1605 (2001) which describes Ampicillin Dextrin Agar with Vancomycin Aeromonas utilize Dextrinin the medium to form acids which are detected by the pH indicator bromothymol blue by changing the colour from blue to yellow.