The centrepiece of Loch Lomond Shores is this aquarium, which has displays on the wildlife of Loch Lomond, an otter enclosure (housing short-clawed Asian otters, not Scottish ones), and a host of sea-life exhibits ranging from sharks to stingrays to sea turtles. It's a lot cheaper if you book online.
Loch Lomond Sea Life
Loch Lomond