It’s not unusual to have disruptions when bring a new animal into a household, especially if you’re dealing with adult animals. Dogs are pack animals and need to establish a pecking order (dominance). You may be able to get this worked out, but I must warn you, some animals never manage to get along.
The first thing that you need to do is establish yourself as alpha dog to the malamute. Obedience classes are a fantastic way to learn about dog behavior, body language, and setting rules in the house. Make sure to find a reputable trainer!
Talk to the trainer about assessing both dogs’ personalities. If your rottie is also a dominant, there may be battles to determine who is top dog. If she’s not a strong dominant, you may be able to get to mal to relax by treating him as top dog – greet him first, feed him first, let him outside first, etc. Again, a trainer will be able to help you with a plan.
You don’t mention if both of these animals have been neutered and spayed. Having intact animals is only going to increase your problems.
There is no simple, quick answer to this issue. You will need to work diligently and consistently. And please take care, these are both large dogs that can do a lot of damage.
We’ve had multiple instances of dogs being brought into the emergency clinic who have lived together for years with minor scuffles who eventually try to kill each other. We’ve also seen owners who tried to intervene and were badly bitten. Hopefully you’ll have a much happier ending.