No, but Ich is something that your fish probably have, you just don't see any signs of it. Unless you have treated for it, then they probably have it and since you are going through all of the trouble of quarantine why not do it 100% instead of 80%.

Anyways...just saying is all. 80% is better than any precautions I take. So, you still get mad props! Just wanted you to know about the other 20% in case you over looked it.