You must be new to fish keeping ich can be in the water just because it's not on the fish doesn't mean the water won't carry ich. Lol you sound very arrogant you do know many lfs don't breed their fish and most are imports. Who knows what they carrY.Why would you be buying or have bought in past fish from a place that had tanks with ich in it is more the question..
No offense to you but you proved my point spot on.
If a person is even remotely doing their due diligence (checking all LFS tanks for ich beforehand which takes about 5 min) then you shouldn't be all-consumed with introducing fish. It should be an easy 30 min floating in bag for temp adjust then in it goes.
Unless obviously you bought fish from a LFS with ich in its tanks.. which is unfathomable.....and obviously your own fault.
You created this thread for no reason. You have your mind made up. Go ahead put the tank water in the tank without a care.
Also the times I have had ich I bought it from hobbyiest from a local group forum and you can't just visually check for damn ich.