Third option, do not take Logan to the dog park. He is a dog that should not be there.
DO NOT use a shock collar to try to stop a fight, it WILL make it worse. The dog being shocked will assume the other dog is inflicting the pain and fight harder.
DO NOT use a shock collar to try to stop a fight, it WILL make it worse. The dog being shocked will assume the other dog is inflicting the pain and fight harder.