I bought a selective medium to isolate bacteria of the bacillus genus (Bacillus chromoselect agar). The colonies looked good and the color corresponded to the manufacturer's recommendations. These colonies were purified and amplified on 16s with primer universals. Then when identifying the sequences, vibrios appeared. This result is possible if the medium in which the colony grew was selective for gram +?

"Product manufacturer's indications: Bacillus ChromoSelect Agar is based on the formulation of MYP Agar formulated by Mossel et al (1) used for enumeration of Bacillus cereus and Bacillus thuringiensis when present in large number in certain foodstuffs. B. cereus causes food poisoning due to consumption of contaminated rice (1,2,3) eye infections and a wide range of other clinical conditions like abscess formation, meningitis, septicaemia and wound infection. The medium contains peptic digest of animal tissues and meat extract, which provide nitrogenous compounds. Mannitol serves as the fermentable carbohydrate, fermentation of which can be detected by the pH indicator phenol red. Mannitol fermenting organisms like B. megateruim yield yellow colored colonies. The chromogenic mixture present in the medium is cleaved by the enzyme β-glucosidase found in B. cereus resulting in the formation of blue colonies. B. thuringiensis will also grow as blue / green colonies on this medium as B. cereus and B. thuringiensis are biochemically identical. If selective isolation of B. cereus or B. thuringiensis is required aseptically add polymyxin B"