I just checked on my first two hives again today. One seems to have tripled in size while the other ones seems to have just doubled in size. Is that normal for one to grow faster than the other?
In a word, yes. It is very normal.
Don't let them get close to the 70-80% capacity or they'll be hanging in the trees. My swarms and smaller hives has very much exploded. Keep an eye on them.
I am putting on another deep next Monday when I finish them up this weekend. I am going to get some framless honey supers soon. Mr. Bushes website convinced me to go frameless.