Asciiquarium is a free and open source terminal command-line Ascii Aquarium application for Linux. It turns your terminal into a underwater world with life. You can use this application as a your terminal screensaver. It is a fun application with not other real usage.
How to install asciiquarium on Ubuntu
It is available as a snap package file from the snap store. In the terminal application (ctrl+alt+t) run below asciiquarium snap install command. It will install the latest asciiquarium on your system.
sudo snap install asciiquarium
After that run asciiquarium using below command.
asciiquarium
If you want to pause the app use “p”, for redraw use “r” and q for quit the app.