How to do a deep clean on a used hot tub?

I recently purchased a used hot tub, it looks like the previous owner hasn't used it in a while or taken very good care of it. What should I do for my initial cleaning before using it? Should I fill it up with water, add a gallon of bleach or vinegar and run the jets and blower for half an hour then drain it? I want to make sure i clean out the plumbing well. (6-7 person tub)