Shocking is as important as regular sanitizing with chlorine or bromine (step 1) and adding algaecide (step 3). All pools need to be shocked on a regular, weekly or biweekly basis. Period.

Shocking your pool weekly helps rid the pool of organic & inorganic wastes such as sweat, cosmetics, suntan lotions, body oils, urine, contaminants brought in by rain or wind or even fresh water that is added to top off or fill the pool.

Almost ALL common pool water clarity problems (including early algae growth, mold & slime) are due to the fact that pool owners don't shock the pool properly - especially at pool opening. Insufficient initial shocking sets the pool water up for "water clarity failure."

Proper shocking helps ensure that the sanitizer (chlorine or bromine) can concentrate on killing bacteria & algae rather than having to fight these other foreign materials. When a pool is properly shocked, the pool stays cleaner & actually sparkles, and is less prone to algae blooms and cloudy water. An added bonus is that you will use LESS chlorine over the course of the average swimming season.

Shocking should be done at least every week or 2 weeks from pool opening to pool closing depending on use & current conditions.

But there’s more to it! Are you shocking, trying to reach “break-point” chlorination or curing a chlorine demand? Let's explain the differences between the 3 needs and the various products used to do the job right.

Regular Shocking.
“Regular Shocking” is just that. The pool is otherwise clean & clear. Algae is under control. There is no haze to the water. When you test the water (done twice each week), the Total Chlorine level is equal to the Free Available Chlorine (FAC) level. There are no Chloramines (chlorine combined with swimmer and organic waste) present.

Regular shocking should be done once every 1 to 2 weeks from the time you open the pool until closing or winterizing. Regular shocking oxidizes (burns out or burns away) swimmer and organic wastes that accumulate in the pool water over time.

These wastes include sweat, urine, lotions, cosmetics, “stuff” that is introduced from the wind & rain. More recently, there is a concern for “stuff” or wastes that are brought in from normal “top offs” of municipal (tap) water or well water. These wastes contribute to red, irritated eyes, hazy water, algae growth, and water that smells like it has “too much” chlorine. Actually there is not enough FAC.

Shocking helps to “re-chlorinate” the chlorine. A properly treated chlorine pool should smell fresh and be sparkling in appearance. Mono-persulfate shocks are OK to use from time to time to oxidize wastes, but chlorine shocks such as Cal-hypo or lithium are the preferred product. Liquid shocks? Sorry, but they are just not strong enough. (11% versus about 50% available chlorine). Household bleach? Save it for the clothes in the laundry! Would you use pool chemicals to wash your clothes?

Typical doses: BioGuard® Burn Out® : (cal hypo) 1 bag per 10,000 gallons (or any part of) every week or 2 depending on weather and usage. BioGuard® Burn Out® 35 (lithium): 1 bag per 6,000  gallons (or any part of) every week or 2 depending on weather and usage. 1 bag = 1 pound. NOTE: These typical doses assume that the water is CLEAR without any visible algae or other problems.

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