The experiment was done to understand the behavior of Aeromonas hydrophila while in aquatic environments and why it has protective effects for some fish compared to others.

 Thirty rainbow trout were placed in tanks, each differing in conditions (nonautoclaved non-filtered, non-sterilized, and autoclaved filtered water). Each tank was introduced to either AG2 or the aroA strain of Aeromonas hydrophila. The bacteria was given time to grow. Cells were taken from the trout and stained to detect the bacteria that had entered and see if they were curable (Vivas, J., et al, 2004).

In the nonsterilized environments, more forms of bacteria grew/were present. In the sterilized water, only the AG2 strain showed any growth while the curability of aroA had declined/became more resistant. In the non-sterilized water, the aroA strain grew initially, but later disappeared (Vivas, J. et al, 2004). These results are shown graphed in Figure 2. 

The findings show that when trying to combat strains of Aeromonas hydrophila, the aroA strain is more able to be cured than the AG2 strand in wild habitats (Vivas, J. et al, 2004).