just built pool and poured concrete yesterday, contractor said (and was backed up by locak supply store) let cure for at least 4wks then use Deck `o`seal it s a 2 part epoxy type of sealant .
Instructions say 1 pack ($50) will do 60 ft at about 1/2 in by 1/2 inch, i got mine from local building supply yard. and will do it myself.