There are advantages to both, and you’ll get different opinions depending on who you ask. Glass tanks are more durable, do not scratch easily and because of their strength they can be set on open top stands, which are more affordable. Glass aquariums have open tops, making them easier to decorate and clean. They tend to be more affordable, especially in sizes less than 300 gallons. Acrylic tanks scratch more easily and some may yellow over time. The entire bottom must be supported to prevent bowing and separation of seams. They are lighter and are available in a wider range of shapes than glass aquariums. They can also be easily drilled to accommodate custom plumbing.