What to do about ammonia in my tap??

[Bettalover29]

So I recently moved and before the move my fish had some pretty bad fin rot but with a lot of maintenance, questions and research they were recovering. Granted they will never fully grow back their very damaged fins because I caught it too late after my vacation. Anyways their fins were going back somewhat and I noticed 3 or 4 days ago after my wc my most healthy fish has lost a lot of her fin. I tested the tap water today and it's 1ppm. Poor things. I have prime and Stability but it seems the ammonia is still a bit high. Should I get some RO water to supplement some of the tap I use?

 

[BigManAquatics]

Whether it is RO water or something else like spring water, using a different source may help. Worth a try anyway.