This was an unusual appplication for a scrolling message display for Para Tech Coating UK Ltd.
The design brief was to make a simple scrolling LED display on a single PCB. The PCB was then treated using a Parylene coating to make it fully waterproof.
The circuit was then immersed in a fish tank as part of a promotional display showing the effectiveness of the coating method.
Note: Please don't try this with your Goldfish at home!