Step five
At this stage, it is time to turn your attention to keeping the water clear, clean and trouble-free. Everyone knows the importance of keeping the pool free of algae. No one wants to pull back a pool cover and be faced with a swamp instead of a nice clean pool. While keeping the pool free of algal slime over the winter is obvious, you should also be concerned about keeping the pool walls free of stains and scale, which can cause corrosion.
If the pool will be covered for the winter with a solid cover, treat the water first with either a chlorine or non-chlorine shock. This will destroy any remaining organic material that may be in the water. If the pool was not treated with chlorine for a lengthy period prior to winterization, you may want to use chlorine to shock the pool, as this will kill any remaining organisms in the water. However, if a chlorine residual is present at the time of closing, it may be better to use a non-chlorine shock. Both will do an excellent job of removing organic matter that could serve to feed any algae that may get into the pool. It is not necessary to shock a swimming pool that will remain uncovered over the winter or use a mesh cover. In this case, the benefit of shock treatment is quickly lost, as organic matter can easily return to the pool via rain or falling debris.
Shocking the pool alone will not prevent algae from causing you grief. The best program is long-term control using a good winterizing algaecide. An effective algaecide can be specially formulated for treating pool water over the winter, or use one known to provide long-lasting algaestatic (prevents growth) activity.
Finally, you want to keep the pool walls and floor free of stains and scale formation. To do this, apply a sequestering agent that is formulated to control metallic stains (e.g. iron or copper) and scale formation. Sequestering agents also provide an added benefit by forming a film on metallic equipment, which helps prevent corrosion (oxidation and pitting), while also limiting chemical degradation (etching) on plaster.
Step six
You may think our work is done after installing the cover, which, to a large extent it is. However, it is also beneficial to periodically check on water conditions in late winter or early spring.
Evidence of algae growth or locating problems with the cover at this point will help you prevent finding a surprise later, when it is time to open the pool. Problems with the cover may be something that can be easily corrected; should you find algae starting to appear, you can apply another dose of algaecide to keep the problem in check. Even though the water may be very cold, algae can still grow.
Following these steps in the fall will make your client’s life easier and enjoyable come spring. If done right, you will be more likely to pull back the cover in March to find the water in good shape, minimizing the amount of work needed to get swimming.
John Puetz is director of technology at Advantis Technologies, an Arch Chemicals Business, based in Alpharetta, Ga. Advantis produces GLB and Rendezvous pool and spa products. For more information, visit www.glbpoolspa.com.
