Fish market on Playa Principal

When you ask about tuna, I am assuming you mean yellowfin tuna (AKA Ahi). The playa fish market is not likely to have YFT this time of year. The covered mercado may have some that has been trucked in, and if they do, you can buy a portion of a fish. The playa fish market will have locally caught skipjack tuna (AKA bonito). A very different eating fish and probably not to your taste.