If you haven't already done so, I'd put a plant or two in the bowl with the fry---just so that they have some cover and aren't so stressed out in the open. Doesn't matter whether it's live or fake plant.
So you'll be moving the fry back to their original tank once you get the new one set up and put the adults in it? Sounds like a good plan.
As for the "white patches" and odd behavior that you described...
Has that gone away? If so, I wouldn't worry about it. Like others said earlier, it was probably brought on by stress as a result of water-changing.
And no, "white patches" does not sound like ich to me.
Ich appears as whitish-colored grains of salt. The "white patches" that you are seeing could be some sort of fin damage that the fish got from being pestered a bit by the male (or, alternatively if it was the male that has the "white patches," it could have been a female that got tired of him pestering her and nipped at him).
I don't mean to ramble on...
If you could provide pics, it would help. But otherwise, I would leave things as is.
Big Vine