NPCs composing that spawngroup :

a_large_barracuda (25%)

a_large_pirahna (25%)

a_large_sea_turtle (25%)

a_large_swordfish (25%)

NPCs spawning around that spawngroup :
(Max range : 100)

powater_a_triloun_water_guardian54, range=71 (-1026,-7,-29)

a_triloun_water_guardian (100%)

powater reef mobs, range=75 (-892,45,-59)

powater front room sharks, range=26 (-957,6,-54)

a_reef_hammerhead_shark (50%)
a_reef_shark (50%)

powater traps, range=30 (-937,22,-61)

a_swarm (10%)
a_swarm (10%)
HatchSpawnPH (90%)
HatchSpawnPH (90%)

powater Monstrous_Sea_Turtle, range=25 (-946,16,-59)