Agreed, one is fine. I think it's scaring the frogs, too, so that's worrying, and the whole parasite thing is a big concern as well, considering how dangerous dropsy is, though I don't think that is spread by parasites. The frogs haven't been out and swimming since I introduced it into the tank, or at least, not as early as is usual. Either that or I've not been staying up late enough. One worrying factor is that these goldfish do come from a store that sells African Dwarf Frogs, which I know for a fact do spread Chytrid.... or was it African Clawed Frogs? Either way, caution is what I'm taking.

I doubt they'll eat the ghost shrimp, the shrimp are tiny, and hard to see if they're hidden. I was a bit concerned about the shrimp attacking the frogs, but I suppose that's just paranoia, since their pincers are TINY

Impaction, I've heard of it. It's similar as to why wool and string should be kept away from cats? It'll mess with their small and large intestines and such?