Macquarium

Ihnatko has mentioned in interviews[1] that he saw attempts to build Macintosh aquariums at trade shows that, among other drawbacks, suffered from noticeable water level lines across the "screen" that spoiled the illusion of a "really good screensaver".

This drove him to design a version without a visible water line, and which allowed the external case of the donor Mac to remain intact.

Because of its small capacity relative to most other aquariums, the Macquarium is considered a form of nano aquarium, which requires a higher level of diligence to maintain proper water chemistry and cleanliness.

For these aquariums, Ihnatko used the case of the Macintosh as the tank and sealed the screen and vent holes to be watertight.

Macquariums are often stocked with 2–3 goldfish, which do not require tank heaters and are cheap.