I have a huge soft spot for them too, one of my first fish as a child was a weather loach. He is about the same size as the babies (I shouldnt keep calling them babies lol they are all grown up now) so he should fit in ok, even up the boys to girls ratio a bit better too, not that I want any more lol. He will have to stay in QT a little longer just to be safe I would hate for him to go down hill if I move him too quick.