There is lye in all bleach or chlorinating liquid since the higher pH stabilizes the hypochlorite. However, this product has more lye than normal bleach so Carl is right that it will tend to raise the pH some. Specifically, one gallon of this product would need around 2.8 fluid ounces of full-strength Muriatic Acid to compensate for the excess lye in it.

However, the main problem with Outdoor bleach is that just like splash-less bleach it also contains thickeners (not listed in the MSDS because they are not hazardous) and these can cause foaming in swimming pools. If this happens, just scoop up the foam from the surface of the pool. And as Carl says, don't use this again.