Your solutions are correct but unnecessary complicated. You can use pure javascript filter function. This is your model:
$scope.fishes = [{category:'freshwater', id:'1', name: 'trout', more:'false'}, {category:'freshwater', id:'2', name:'bass', more:'false'}];
And this is your function:
$scope.showdetails = function(fish_id){
var found = $scope.fishes.filter({id : fish_id});
return found;
};
You can also use expression:
$scope.showdetails = function(fish_id){
var found = $scope.fishes.filter(function(fish){ return fish.id === fish_id });
return found;
};
More about this function: LINK