HTH 52031 Swimming Pool Care Shock, Swimming Pool Chlorinator Boosts Chlorine Levels, Cal Hypo Formula, 13.3oz

If you are looking for a straightforward way to keep your pool or hot tub inviting, the HTH Shock Ultra is a highly effective choice. This fast-dissolving, 4-in-1 formula is designed to solve 90% of common water problems within 24 hours, making it a staple for regular maintenance. I buy these every couple of months because they work wonders for both in-ground pools and hot tubs. The Cal Hypo-based formula is a standout because it sanitizes without adding cyanuric acid (CYA), which helps you avoid "chlorine lock" and keeps your water chemistry balanced longer. Why this shock treatment is a great choice for your maintenance routine: Restores Clarity Quickly: It effectively kills bacteria and algae while reducing the strong chlorine odor and eye irritation often found in busy pools. Multi-Functional Performance: This treatment not only sanitizes but also provides a visibly brilliant sparkle to the water by removing organic contaminants. Universal Compatibility: It is safe for use in all swimming pool types, including vinyl-lined pools and saltwater systems, providing peace of mind regardless of your setup. Convenient Weekly Use: Designed for easy application, this shock treatment helps you maintain a healthy environment for your family with minimal effort. I haven't had any issues with packages arriving broken or anything leaking out in the box. This 6-pack lasts me about 2 months as I use it for an in-between.

I used this last year after coming home from a long international trip to a completely green pool and really I was impressed with how well it worked. My pool had been neglected for over two weeks while I was away and by the time I got home the water was fully green with visible algae growth. I added two bags of this shock around the perimeter of the pool in the evening with the filter running and brushed the pool afterward to help make sure everything dissolved completely. By the next morning, the pool had already changed from swamp green to a cloudy blue. It was not crystal clear yet, but the algae was clearly dead and the transformation overnight was dramatic. At that point I backwashed and rinsed my sand filter and a crazy amount of algae flushed out. I continued filtering nonstop, brushed the walls again, skimmed debris, and used socks over the inlet ports to catch the finer dead algae particles. Throughout the day the socks kept collecting thick layers of fine algae residue so I rinsed them several times as the filter continued running. By the following morning I could clearly see the liner pattern at the bottom of the pool again. After another day of backwashing, brushing, vacuuming, skimming, and filtering, the pool was completely clear and ready for the family to enjoy again. I think it’s important to mention that bringing a green pool back takes patience no matter what brand of shock you use. This is not an instant one-hour fix but the product absolutely did its job and worked quickly once the filter system had time to remove all the dead algae. For reference, I used this in a soft sided above ground pool with a sand filter system. The attached photos show the pool before treatment, the morning after shocking, the second day of filtering and cleaning, then the final clear result on day 3. Pros: Worked quickly on a severely green pool Noticeable overnight improvement Killed algae effectively Dissolved well after brushing Worked well with a sand filter setup Cons: Restoring a neglected pool still takes time and repeated filtering/backwashing

It works perfectly to keep my pool clean

This pool shock works really well! It cleared up the water quickly and helped keep everything clean and balanced. Easy to use and does exactly what it’s supposed to. I’ve noticed a big improvement in water clarity after using it, and it’s been reliable every time. Great value for the price and a must-have for pool maintenance. Highly recommend for anyone looking to keep their pool in great condition!

I had this stubborn black mold looking stuff in the rubber seal around my washing machine from previous owners. I had tried everything!! Bleach, vinegar/baking soda, intense scrubbing, endless cleaning cycles, the tablets made for cleaning washing machines, etc. Nothing worked. This stuff did. Obviously be careful though, it's very potent.