So, I was brushing the walls of my Pebble Fina pool the other day and noticed a small brown spot about the size of a dime on the wall near my vacuum port. Brushing with a stainless steel brush and running a pumice stone over it did nothing, and holding a trichlor puck on it for 15 minutes did nothing. Putting ascorbic acid on it had no effect, so I was baffled. I tried sending some muriatic acid down a flexible length of 3/4" diameter sprinkler hose and that seemed to remove a thin layer of plaster, revealing an embedded piece of stick or leaf stem about 1/2" long. I removed this and cleaned out the small indent and the spot is now gone. I'm guessing this would be considered a defect by the applicator of the plaster? Can/should this be filled in to prevent issues with the plaster going forward? I have other cosmetic issues raised with the company who applied the Pebbletec finish (obvious light/dark variations following trowel marks...most likely due to adding water while troweling), so I wonder if they can fix it. The finish is just over one year old.