The text of the logo is recognizable even in water. With glycerin I think it will be even nicer looking.
I’m actually cheating by rendering text as a bitmap image and then using software to load the bitmap into the arduino. So really, this is a video that demonstrates my ability to display arbitrary graphics, not actually generate text. (But I do plan on embedding a simple font table in the arduino so that the arduino can just render generic text.)
Did you have any problems with the tubing going to the check valve getting fluid in it creating irregular bubbles?
Only if a tube had not sent out a bubble in the last 20-30 seconds. The liquid would slowly go into the tube, but it took several tens of seconds before it became an issue. I would have all the motors blow out a single bubble (one horizontal line) any time I was starting a new pattern after a bit of rest. And the system will blow a line of bubbles out every 30 seconds even when idle.