Here is the full list of all 11 Ace of Seafood achievements.
Defeat Super Synthesis Fish using sardine only
Repel fish invaders
Defeat Super Synthesis Fish
Occupy all reefs
Defeat a GiantSquid
Occupy 'Charcoal stove'
Occupy ’Bathtub of blood’
Occupy 'Deserted house'
Occupy 10 reefs
Sink a warship
Occupy a reef