Of the many challenges involved in sustaining economically-viable aquacultural operations, consistent quality and flavor of farmed fish products may have the largest potential to influence consumer preferences. In particular, occurrence of “musty” or “earthy” flavors in fish is undesirable and decreases product values. 2-Methylisoborneol (MIB) and geosmin (GSM) are often responsible for these off-flavors, and accumulation in farmed fish can be both rapid and sporadic depending upon the microbial content of rearing waters. Although much effort is involved in removing MIB and GSM prior to harvest, fish fillets with detectable levels of MIB or GSM can occasionally reach consumers. Strategies for post-harvest off-flavor removal must consider the overall quality of the final product, so harsh treatment conditions involving chemical oxidants are not practical. Fillet treatments involving marination in weakly acidic media have been reported to reduce the off-flavors in fish, though the exact conditions and optimal parameters have not been defined. MIB and GSM degradation in weakly acidic water containing ascorbic, citric, and maleic acid were evaluated and quantified using instrumental analyses to assess the practical feasibility of post-harvest off-flavor removal in fillets. 1000-fold reduction of MIB concentrations were observed at pH 2.4, while only moderate GSM degradation occurred at pH values below 2. Near-complete regeneration of MIB and GSM upon neutralization of acidic solutions was observed, suggesting limited efficacy of acidic treatments in off-flavor fish products.