How did they manage? To keep the fish tasting fresh, the Japanese fishing companies still put the fish in the tanks but with a small shark. The fish are challenged and hence are constantly on the move. The challenge they face keeps them alive and fresh!
Have you realized that some of us are also living in a pond but most of the time tired and dull? Basically in our lives, sharks are new challenges to keep us active. If you are steadily conquering challenges, you are happy. Your challenges keep you energized. Don't create success and revel in it in a state of inertia. You have the resources, skills and abilities to make a difference.