7 Fish for one Ship?
holy crap..
I play With GW mod in the career and I mostly aim my Fish at her Engine compartment. just to get her Dead in the water. then I just watch the ship leaning towards one side and blast an 2nd fish into under her Bridge (also known as Command tower) On an lucky shot the ship breaks in 2 parts or she blows up but mostly she just roll over and sinks.
the only times I would fire more then 4+ Fish is into an big bad Battleship...because those are defently worth it