Quote Originally Posted by bsol View Post
Identification?
Well... You haven't gotten anyone jumping forward with a positive ID, here... I guess the best I can say is it's not a guppy. It does resemble a rosy red: Robyn's Rosy Red Page. Same general body shape, same fin count & placement. Maybe an aquarists' forum would give you a better ID? (Incidentally, toward the bottom of that page I linked to, the author mentions people sending them pictures for ID... I can't vouch for their qualifications or anything, but you could try sending your pic there.)

The plain or golden white cloud minnows I've seen in fish stores also look similar, I think they're sometimes sold as feeders too.

I've seen everything from "rosy reds have as much thiaminase as goldfish" to "rosy reds are fine" (on someone's garter care sheet no less!). But never any actual scientific sources for the claims, of course. Much less info in general about white clouds, but they're cyprinids too so the safest guess is that they also have the potential to contain thiaminase.