In our previous investigation, we showed that early start of aeration delays and mitigates negative effects of white spot disease on cultivated L. vannamei ( Ruiz-Velazco et al., 2010). Deposition of bottom sediment occurs gradually before aeration is started and, compared with an early start of aeration, a late start provokes more suspension of sediments and lowers mean dissolved oxygen. This leads to depressed respiratory activity and greater vulnerability in infected shrimp when dissolved oxygen is low. We found that, under normal operating conditions and contrary to what was initially hypothesized, starting time of aeration was of minor importance in controlling shrimp production, compared with other management factors. This reversal of expectations is most likely related to the reduced sensitivity of healthy shrimp to low dissolved oxygen and poor water quality following removal of pond bottom sediments.