These color additives mix with foam solution before going through the foam machine. It's a liquid mix so it falls off of the bubbles. It comes out of the machine in the color you add and then goes away quickly. Color lasts longer on smaller and tighter bubbles. One bottle mixes with 50 gallons of water when using the pump or 5 gallons when using the siphon. Yes. You will experience some staining.
Save money. Don't buy the color dye for night events. Light the foam with colored lighting. Make a smaller mess by using lights and skip the color dye all together! For U/V and a glowing foam effect you simply use lighting. Foam additives (including color dye) are not necessary.