I used to try painting with hibiscus tea. Every time the bright red color turned to blue as soon as it got to paper. I have tried all kinds of paper, photo copy or water color, but there was no exception. It turned blue.
I thought it was the basic chemical (碱性化学品)in the paper that make this. So today I added the juice of half a lemon and boiled it.
Still, it came out blue.
I fail to understand why.