10 Best Pool Chemicals 2025 in the United States

The HTH 52040B Swimming Pool Care Shock Ultra is a strong choice for pool owners who want a reliable way to boost chlorine levels and keep their water clean and clear. Its calcium hypochlorite formula works quickly to kill bacteria, prevent algae growth, and reduce staining and scaling, which helps maintain a sparkling pool. Unlike some pool shocks, this product doesn’t add cyanuric acid, so it avoids the risk of chlorine becoming less effective over time, a problem called chlorine lock. The visible blue color when applied helps you see that it’s working, which is a handy feature. It’s suitable for all types of pools, including vinyl-lined and saltwater pools, making it versatile.

The HTH 52037R Pool Care Shock Advanced is a versatile and effective pool chemical designed to address a variety of common pool water issues. Its 4-in-1 formula is a notable strength, as it kills bacteria and algae, reduces chlorine odor and irritation, and restores water clarity quickly. This makes it a convenient option for weekly maintenance, solving most pool water problems within 24 hours, which is ideal for busy pool owners looking for a quick solution.

The HTH 52036R Pool Care Shock is a fast-acting, multi-purpose shock treatment designed to keep your pool water clean and clear. Its 4-in-1 formula targets common pool issues by killing bacteria and algae quickly, reducing chlorine odor and irritation, and restoring sparkling clarity within 24 hours. Because it uses a calcium hypochlorite base without adding cyanuric acid (CYA), it avoids the problem of chlorine lock, which can happen when too much stabilizer builds up. This makes it suitable for all types of pools, including vinyl-lined and saltwater systems.