 If you find that, there are toilet flappers. The brand name is called Corky. They're red. And those are chlorine resistant. So they don't break down. So I don't know, maybe you have a high content of chlorine that's causing that. Is that stain, is that easily removed in the toilet bowl? Yeah, yeah, you can come, you know. Maybe it's like a barkeeper's friend or something like that.