What Kind of Salt Is Needed for a Swimming Pool Salt Water Filter?
- Salt water pools do use salt, but the salt itself does not kill any organisms. Instead, as the water passes through the filter, an electrolysis process tears the salt molecules apart and uses their chlorine to kill organisms in the water, before cycling it back into the pool. The chlorine stays within the filter and the water in the pool is filled only with salt unless the filter system is being run.
- The salt used for saltwater pools must be sodium chloride. Table salt is mostly sodium chloride, but the fewer additives in the salt the better. Most filters give information regarding the quality of salt to be used. For instance, many filters require 99.8 percent pure sodium chloride. Swimming pool companies often provide bags of salt with the necessary purity levels that you can use.
- Salt levels tend to stay around 2500 to 4000 parts per million parts of water. This is much less than saltwater from the ocean and is rarely noticeable as a taste by people who use the pool. Many companies claim that this small amount of salt actually has a refreshing or soothing effect.
- Saltwater filters and salt-chlorine generators do not always require salt replacement. The salt is not used up and does not fade away like chlorine chemicals. Only when the pool is emptied and the water is replaced will the homeowner need to add more salt. In hot climates, if enough water evaporates then some salt may need to be added to the pool.
- In addition to pure salt, pool owners can also use what are known as water conditioning salt pellets. These small pellets are dropped into the water, where they begin to dissolve and circulate pure salt into the water. These pellets take longer to affect the entire pool than if you use normal salt crystals. Iodized or yellowish salt should never be used, because they will contaminate the filter and cause build-up problems in the pumping system.