I'm only asking cause I've never heard of it. My boyfriend's 17 year old daughter came home high last night and told me she had been smoking hydro. She begged me not to tell her dad and that she'd never do it again. I was tired and told her I wouldn't unless it happened again. I mean I know we can all make mistakes and do things we wouldn't normally do especially if we are under peer pressure. But I don't know what Hydro is and now I'm not so sure I shouldn't tell her dad.