Salt Water Pools

How to Shock a Salt Water Pool

A salt pool is a chlorine pool. When it needs a shock, add chlorine by hand and let the cell rest.

Updated November 2026

Short answer

Shock a salt water pool the same way as any chlorine pool: add chlorine directly, and liquid chlorine is the best choice. The salt system's boost or super chlorinate button is fine for a small top up, but it is far too slow to clear algae or cloudy water.

How much you need depends on your stabilizer level, which some salt system makers set higher than for other pools.

Shock calculator

Enter your pool size, chlorine and stabilizer readings to get the dose.

Which shock should I use in a salt pool?

Shock options for a salt water pool compared
Option	Good for	Watch out for
Liquid chlorine	Algae, cloudy water, routine shock	Nothing extra. It adds only chlorine and a little salt
Cal-hypo shock	Algae and routine shock	Adds calcium, which builds scale on the salt cell. Add it exactly the way its label says. Some labels forbid premixing it in a bucket
Dichlor shock	Occasional use	Adds stabilizer. Avoid it if stabilizer is already 60 ppm or more
Boost or super chlorinate mode	A small bump after a party or heavy rain	Slow, and it uses up cell life. Not strong enough for algae
Non-chlorine shock	Clearing dull water between chlorine shocks	Does not kill algae

How do I shock a salt water pool?

Test free chlorine, pH and stabilizer (CYA). Lower pH to about 7.2 to 7.4 first, because chlorine works better there.
Work out the dose. The shock level rises with stabilizer. At 70 ppm of stabilizer, the target is about 28 ppm of free chlorine. The shock calculator does this for you.
Brush the walls and floor so chlorine can reach the algae.
Add liquid chlorine in the evening, slowly, in front of a return jet with the pump running.
Keep the pump running around the clock and retest every few hours. Add more chlorine to hold the shock level.
Stop when the water is clear and chlorine holds overnight. Then clean the filter and let chlorine drift back to normal. Keep everyone out of the pool until free chlorine has dropped back to 4 ppm or below, the level chlorine shock labels require before swimming.

Never add acid and chlorine at the same time or in the same spot. Add acid first, wait at least 30 minutes with the pump running, then add chlorine.

Should I turn the salt cell off while shocking?

Check your manual. In their start-up instructions Pentair and Jandy both say to shock with added chlorine and leave the salt system off until chlorine is back to its normal range (2 to 4 ppm for Pentair, 1 to 3 ppm for Jandy). Turning the cell off during a shock costs you nothing, because it adds very little compared with what you are pouring in. Turn it back to its normal setting when the shock is over.

If a salt pool keeps going green, the cell is not keeping up. Common reasons are a setting or run time that is too low for summer, scale on the cell plates, low salt, cold water, or stabilizer that is too low to protect the chlorine it makes. The salt water pool care guide covers each one.

Frequently Asked Questions

Can you put shock in a salt water pool?

Yes. A salt system makes chlorine from salt, so the pool is already a chlorine pool. Adding chlorine shock by hand is safe and is the normal fix for algae.

Is boost mode the same as shocking?

No. Boost runs the cell at full output, usually for 24 hours. A cell matched to the pool makes only about 4 ppm of chlorine in that time, an oversized cell perhaps twice that, and sunlight uses part of it up. A real shock for algae needs a much higher level, added all at once.

How often should I shock a salt water pool?

Only when it needs it: after heavy use or a storm, when combined chlorine tests at 0.5 ppm or more (the pool industry standard is to keep it at 0.2 ppm or less), or at the first sign of algae. A salt pool that holds its chlorine does not need a weekly shock.

Why is my salt pool green when the salt level is fine?

Salt level only tells you the cell can work. Check free chlorine and stabilizer. The usual causes are output set too low, a scaled cell, or stabilizer below the range in your system manual. That range is 30 to 50 ppm for Pentair IntelliChlor and Hayward AquaRite, 50 to 75 ppm for Jandy AquaPure and 60 to 80 ppm for CircuPool RJ.

Will shock raise my salt level?

A little. Liquid chlorine and other chlorine products leave salt behind as they are used up. It is a small amount and rarely needs correcting.

Sources

Get the dose right the first time

Too little chlorine and the algae comes back. The calculator gives the shock level for your stabilizer reading.

Shock Calculator Salt Water Pool Care