The Morris Plains youngster may have had a medical emergency shortly after 2:30 p.m. July 6, they said.
"Staff noticed immediately, pulled the child from the pool and conducted CPR," Clifton Police Detective Lt. Robert Bracken said.
The child then began breathing again, the lieutenant said.
He was conscious and alert after being taken to St. Joseph's University Medical Center, Bracken said.
Click here to follow Daily Voice Mahwah-Ramsey and receive free news updates.