Does vinegar lower the pH in a pool?

No, vinegar will not effectively lower the pH in a pool. While vinegar is acidic and can temporarily decrease the pH, it is not usually advisable to use vinegar as a pH reducer in pools.

Here's why:

1. Weak Acid: Vinegar (acetic acid) is considered a weak acid, while pool water often requires stronger acids to significantly alter the pH. Stronger acids like hydrochloric acid (muriatic acid) or sodium bisulfate are commonly used for pH reduction in swimming pools.

2. Buffering Capacity: Pool water contains alkaline substances, such as calcium and bicarbonate ions, which act as buffers. These buffers can neutralize the effects of weak acids like vinegar, preventing them from effectively lowering the pH.

3. Temporary Effect: Vinegar's effect on pH is temporary. As the vinegar reacts with the pool water, the buffering capacity of the water can gradually neutralize its acidity. This means the pH may rise again after some time, requiring additional treatments to maintain the desired level.

4. Scaling: Using vinegar regularly in pools may lead to calcium scaling. The dissolved calcium ions in the pool water can react with acetate ions from the vinegar, forming scale deposits on pool surfaces and equipment.

For these reasons, it is generally recommended to use specific pool pH reducers or balancers designed for maintaining proper water chemistry. These products are formulated to effectively and safely adjust the pH levels in swimming pools, avoiding the potential drawbacks associated with using vinegar.