i have a 6 year old male rottweiler that i would like to breed.

Read the first post on the breeding forum. 

To be honest no reputable person will ask to use your dog unless he has an outstanding show record or is of rare bloodlines.  He will need to have been hip scored with a good result.

It is the bitch owners who choose which stud to use based on what they see of him at shows and the quality of the pups he produces.

Your boy would have to be measured up against the competition.

Six years old is a bit old for most people to considre using a maiden dog.  His breeder may know of someone interested in a dog of their lines, so I would contact them in the first instance after he has had his Hips score results and had any other breed specific health tests.