Shock dosing breaks down the chloramines, sweat and organic load that ordinary sanitiser cannot reach. A weekly shock keeps water fresh, clear and odour free even with heavy bather use.
Which shock treatment to reach for: weekly upkeep with non-chlorine shock, or recovery of neglected water with chlorine shock.
| What matters | Non-chlorine shock (MPS) | Chlorine shock (calcium hypochlorite) |
|---|---|---|
| Best for | Weekly upkeep after normal bathing | Recovering cloudy, green or neglected water |
| How it works | Oxidises bather waste so your sanitiser is freed up to disinfect | Raises free chlorine sharply to kill bacteria and algae outright |
| Effect on your sanitiser | Adds no chlorine; also reactivates spent bromide in bromine tubs | Adds a large chlorine dose on top of your routine level |
| Time before bathing | Short; retest and bathe once the water has circulated | Wait until free chlorine falls back below 5 ppm |
| How often | Weekly, and after heavy use or guests | Occasionally, when the water needs a reset |
| Typical cost per treatment | Low; a small regular dose | Low; a stronger dose used far less often |