The investigators also found frozen stargazer fin fish, rock lobster, wrasse fin fish and school shark, frozen blue cod and hoki, which the company was unable to provide invoices for.
MPI's regional manager of fish compliance, Garreth Jay, said at the time of the inspection, the company had already been issued a direction by the authority to keep and maintain a fish sales system and to be provided education by fishery officers.
"When a seafood supplier lacks the proper invoices, it creates questions over the legitimacy of what they're doing - in this case, providing fish meals in restaurants," Jay said.
"To prevent this kind of illicit trade in seafood, robust record-keeping is required under fisheries law so that Fishery Officers can ensure it comes from a legitimate, sustainable, and hygienic source.
"A lack of good record-keeping can undermine our quota management system and catch limits which are set to ensure sustainable fisheries.
"When MPI finds evidence of these important rules being ignored - it will investigate and hold people and businesses to account where there is evidence of deliberate offending."
Jay said keeping proper records also assures customers that the seafood in their meals is safe and sustainably sourced.
Chan Farther and Son Limited has been ordered to pay $10,400.
Jay said if anyone was aware of any suspicious fishing activity they should contact MPI on 0800 4 POACHER (0800 47 62 24) or email ncc@mpi.govt.nz.
- RNZ