Please neuter your dogs and don't let them breed! Please don't cage up your dogs because this is cruel. Dalmatians are big dogs and need to be out to exercise.

Eileen is right! Neutering your intact dogs would very likely solve your aggression problems. Also, Dalmatians are prone to congenital deafness. Are your dogs deaf? Poor hearing often results in aggressive behaviour, because the dogs don't hear others approaching and are startled.