Fast growth is not healthy growth in large-breed puppies. Excess energy intake and excess calcium are both associated with developmental orthopaedic disease.
Feed measured meals against calculated energy needs rather than leaving food available all day. Recalculate every two to three weeks as body weight changes.
Keep calcium within a controlled range instead of adding supplements on top of an already balanced diet. More is not safer here.
Track body condition score and growth curve together. A lean, steadily growing puppy is the goal.