Why do they still dye the rivers green for St. Patricks Day? It's not a good look for downtown Chicago.
I just think the novelty of these type of displays was up in the 90s, It's time for an upgrayedd. I propose leprechauns flying up and down the river wearing water jet packs, shooting people with their Chicago-style hot dog cannons would be more with the times. What's your idea?
The first Amazon result says a gallon works for 12000 (1.2 x10^4). So 3 x 10^(16). But that might be just for "detectable", so more to be obviously green.