you may know her, Bill...her name is Lisa Darmo (LisaD on most forums), and is a very sharp buddy of ours. IIRC, she holds a Ph.D. in some type of biology (marine i believe), but is very quiet about her credentials. we know her from the SH forum, but she's an oddball fish enthusiast as well...
here's what she said:
"My boxfish had crypto at one time, and I ending up treating the DT with quinine sulfate. It cured the crypto, and I lost no fish, but the corals were toast. Of course, the emp angel I had grown up/QT'd in that tank a couple years before ate every zoanthid, and my dogface puffer ate all the mushrooms, so there wasn't all that much left. smile.gif I have not ever tried copper or formalin on boxfish. I have treated crypto and velvet in puffers with formalin dips and that has worked fine. There is a nasty crypto going around that doesn't respond to hypo, so I hardly ever even try that any more."
i remember her telling me she uses quinine sulfate now that she mentioned it...