Plaster maximum thickness should be no more than 1". Most plaster thicknesses when applied are 1/2"-3/4" .

The SURFACE must be at least 50 degrees when the plaster is applied. I recommend, and we always do, have water trucked in to fill the pool as quickly as possible. Water is part of the curing process for plaster.

It's especially important to fill quickly on a hot day as there is a concern the plaster will "flash" and dry too quickly in the sun. Some cracks or crazing may occur.

You PB should have considered the material thicknesses prior to shooting the pool so the shot crew could be directed as to heights in areas where the stone was to be placed.