Salt water chlorination is a method of cleaning and sanitizing swimming pools without handling and storing traditional pool chemicals. Pool salt and regular table salt have similar properties, but are not necessarily interchangeable.

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This pool may be treated with pool salt.

Salt Water Chlorination

Salt chlorine generators use pool salt to create chlorine and disinfect pools. When the salt dissolves in the pool water, the chlorine generator subjects it to electrolysis, which separates the salt into sodium and chlorine. This process results in a clean pool without the harsh effects of traditional chlorinated water, like burning eyes, itchy skin and a strong "bleach" smell.

Chemical Structure

Pool salt and table salt both consist of sodium chloride (NaCl). However, pool salt tends to be more thoroughly refined. This enables it to dissolve quickly in pool water, which helps the pool's chlorination system break it down into chlorine. Also, pool salt doesn't contain the iodine and anti-caking agents found in many table salts.

Pool Salt Additives

Some forms of pool salt contain additives that make them toxic and inedible. Common additives include sodium cyanurate or cyanuric acid (a stabilizer that prevents chlorine from evaporating due to sunlight), metal deactivators (to shield the pool surface from metal buildup) and pool water conditioner (to balance the pH of the pool).