I just looked up medical records for my guys. I don't have height. Sophie was 63 lbs at 6 months, Syrus 67. He is usually about 3 - 4 pounds heavier than Sophie. Sophie is broader especially across rump. Syrus is taller and leaner. Now at 11 months, Sophie is 110, Syrus 114. They seem to have stopped growing to me. And I think they are small for Newfs. Then I take them to the dog park and see comparison and they are big pups.
My daughter was visiting with her friend last weekend and when I see them next to the pups, again I see they are rather big. And, they do still have some growing to do. Last pic is Sophie stepping on my daughters foot.

Seems like Tank is pretty much on track.