One the Ich has fully gone from the fish (no visible white spots), allow the tank to settle for anywhere from a week to a month (some people quarantine their tanks or store-bought fish for up to a month)
So, it's up to you. If you think the Ich is not longer there after two weeks, then introduce your frogs then. Just make sure that the water is safe (both in temperature and water chemistry) before you put them in.
Also, I know for certain that a lot of people are going to tell you that it is not best to keep ACF with fish. Some people say they've had no problems but others will tell you that you should never mix the two. Either the fish will be eaten, or the fish will harm the frogs. I'm not going to tell you what you should do, but you have to be aware that the worst could happen, although it may not ALWAYS happen.
hope this helped,
Necro