A cassette for use with an ophthalmic surgical pump for collecting aspirant fluid and tissue from a patient's eye includes a rigid walled container having an interior volume. At least one tapered alignment slot is formed in a side wall of the container and extends from a back wall towards a front wall. An irrigation and aspiration manifold base is removeably attached to the container. An aspiration path is formed within the container for receiving the aspiration fluid and the tissue from the eye and directing the flow of fluid towards a front half of the container before the fluid and tissue collects within a majority of the interior volume of the container. A fluid level indicator is formed on a wall of the container, such that an associated photo-detector of the pump may determine a level of fluid in the container.
