Only silver fish I have with mine is a bala shark and he chases him maybe once a day but never left a bite mark, but they're said to not like other silver fish. I wouldn't go and say necessarily that the armatus would be out right killed, but it's possible. It's also possible that the armatus, if deciding to defend itself, can make a fatal blow as well. And as others have stated as the armatus grows the Odoe can be a potential meal, though ime, most fish, when grown together or introduced after a possible meal, don't eat them. So having the Odoe first and if they don't kill eachother and grow together, I doubt the armatus would eat the odoe. But there's always a possibility.