Our pool was finished in November except for the plaster and water, I have been noticing this effervescence coming through the pool walls and through some of the joints on the face of the hot tub. I took a wire brush out and tried to scrub it off the rocks and mortar but its pretty stubborn. Does anyone know if this is a potential problem. PB says not to worry its normal. I don't want the nice stonework on the hot tub to be ruined by this.