Abstract: The invention provides a production method for purified recombinant proteins of commercial value prepared in enclosed aquatic systems. The production system provides biosecure containment of genetically engineered aquatic organisms for an alternative production method for complex proteins requiring post-translational modification that is best done in eukaryotic expression systems. Possible aquatic organisms that can be utilized by this invention are crustaceans (e.g. penaeid shrimp or Artemia) and teleost fish (e.g. trout or tilapia).