The watchwords on properly curing a gunite coating on your pool are "slowly" and "with moisture." Gunite is a dry, powdered cement and aggregate mix sprayed onto a pool underlayment structure, typically metal rebar and mesh, under high pressure. The cement mix meets water and other liquid binders as it exits the spray hose nozzle to make a moist, but firm, paste that clings to the underlayment. The gunite is sprayed on in layers to make a smooth continuous surface on the pool walls and floor. Before a pool can be plastered and filled with water the gunite must thoroughly cure under proper conditions or cracks and other failures of the coatings may result.
Apply and cure your gunite pool coating only when ambient temperatures are well above freezing. If frost is on any portion of the underlayment structure, wait until the frost is gone before proceeding. Trying to apply or cure gunite near freezing temperatures can affect curing strength and a sub-par installation result may occur.
Keep the gunite surface lightly and evenly moist from the time the top surface has hardened and for at least seven days thereafter. You want the gunite to dry and cure slowly so it does not shrink, crack or lose grip from the underlayment and long term problem-free performance.
Spray the gunite surface evenly, with a hose and nozzle adjusted to a mist spray or gentle rain, at least four times a day for at least five to seven days. Stand on the edge of the pool to do this and do not walk into the pool or on the gunite surface for at least three days. Never use a strong jet or pounding spray of water as this can pit and ding the gunite surface. Water enough so that the gunite is wet and a little water rolls down the sides of the pool interior collecting on the bottom.
Allow at least five bright sunny days or seven average days for the gunite to cure before proceeding with finishing steps such as coping, surrounding stonework and pool plaster.