How to do a water unity ceremony?

Has anyone done a water ceremony? (similar to sand. But using individual water vessel that combine to one). I've been looking up this idea but haven't been able to find how it's actually executed? I can figure out how to combine 2dyed glasses of water but I'm looking for a twist. I don't really want to just do red+blue=purple. I've seen photos of things that seemingly look like water change colors, but anytime I look for a how to guide for the water ceremony I get results for the sand ceremony. I'd love to get different ideas.

Thanks so much.