Shock isn't a sanitizer — it's a separate step. Sanitizer (bromine or chlorine) keeps water safe from bacteria. Shock (oxidizer) breaks down what sanitizer can't: body oils, lotions, sweat, and other organic waste that builds up over time.

When to shock

• After heavy use or a get-together

• When water looks cloudy

• When there's an unusual odor

• As general practice, many owners shock about once a week

Which one

• Enhanced Shock (chlorine-based, included with chlorine kits) — does four jobs in one: oxidizer, clarifier, flocculent, buffer. No premixing needed.

• Spa Shock Oxidizer (non-chlorine, included with bromine kits) — dissolves instantly, oxidizes without touching your bromine level.

How: cover fully off, jets running, add per the label.

Don't overdo it

More shock isn't better — over-oxidizing the water fades plastics and breaks down the underside of your cover over time. Stick to the label and roughly weekly is enough for most spas; if you're shocking more than that and still fighting cloudy water, the problem usually isn't a lack of shock.