A small chain of family-owned restaurants in San Diego sells fish tacos for just $1.19. They’ve been selling the tacos that cheap for most of the chain's 13 years. How do they stay afloat? We decided a tasty investigation was in order.

<p>A small chain of family-owned restaurants in San Diego sells fish tacos for just $1.19. They’ve been selling the tacos that cheap for most of the chain's 13 years. How do they stay afloat? We decided a tasty investigation was in order.</p>