An aquarium in a house, office, etc. might represent:
- A self-contained world separate from reality, "living in a vacuum," or a mock-up or artificial environment
- Prison, lack of freedom, limitations forced upon someone
- Feeling cooped up, constrained, unable to change your situation, or hopeless
- Trying to create a situation outside a context where it would naturally occur
- Limiting or manipulating others for one's own entertainment, or playing God