present perfect or simple?

Karen Cookson always is interested in the sea .When she was ten her mother bought her an aquarium and she had a collections of tropical wish ever since then .For the last twenty years , lived in big house in Auckland where she has an aquarium . Last year she opened the aqusrium to the publick. Thousands of people have visited her collection already . Her collections includes several sharks which swim around looking danderous . 'I never have any problem with my sharks becouse I know how to behave . Sharks only attack humans in certain situatons.