Epson salt is good for paw pad injuries like that. The pool deck was probably nonslip coated which is rough on paws. My old guy cut his foot on some glass and I was worried it wouldn't heal but my vet had me use Epsom Salt. I dissolved the salt in warm water then sat on the floor with my dog and used a sponge to hold the Epsom Salt water on his foot. At the sponge cooled off I would resoak it and wring it out and continue. The water stays warm for awhile but he would have no part of sitting with his foot in the water so the sponge idea was born and it worked quite well. His foot healed quickly and didn't get any infection. Good luck with you puppy paws.
Snake Vom Eselspfad RN CGC (AKA Raina) 3/5/08
Pyrate CGC 4/1/03-5/16/12 RIP
Too many to list waiting at the bridge but remembering them all