Photographs of microbial aggregates with and without oil or Corexit collected from four different mesocosm treatments

Mesocosm experiments were performed with seawater collected from the Northern Gulf of Mexico (NGOM) and “seeded” with microbial populations collected from Galveston Bay, TX. Four treatments were set up in triplicate (A) Control, (B) water accommodated oil fraction or WAF, (C) water accommodated oil fraction with Corexit 9500 or CEWAF, and (D) a 10-fold diluted equivalent of (C), called DCEWAF.