you won't need to use super glue or anything. Just like stated before, just like lego, find where they will fit together and balance.
just a couple picture of my 75 gal tank.
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and a couple picture of my 180.
All the rock in both tank is just stacked and balanced on each other. The rock in the 75 has been like that for three years.
Plus from time to time, you may get a new coral and need to move a rock or two to get it to fit into place.
Just be patient and take your time.