You add a pH increaser on Monday. The reading looks perfect by Tuesday. By Wednesday, it had dropped right back to where it started. Sound familiar? This is one of the most frustrating cycles in pool ownership. You feel like you are doing everything right, but the water chemistry simply will not hold. The pH keeps sliding down, and no amount of adjustment seems to make it stick. The problem is almost never the pH product you are using. It is something deeper that most pool owners overlook entirely: your total alkalinity is too low to support a stable pH.…