Dichlor vs. Cal-Hypo Shock: What’s the Difference?

Not all pool shock is created equal. Before adding any shock product to your pool, its important to check the active ingredient on the label.

Dichlor Shock: Sodium Dichloro-S-Triazinetrione Dihydrate

• Adds chlorine quickly to the water.
• Also adds cyanuric acid (CYA), also known as stabilizer or conditioner.
• If you use trichlor tablets or the Frog Leap system, your pool is already receiving CYA on a regular basis.
• Too much CYA can make chlorine less effective, leading to water quality issues and increased chemical costs.

Important: The only way to reduce CYA levels in the water is by partially draining and refilling.

Cal-Hypo Shock: Calcium Hypochlorite

• Adds chlorine without increasing CYA levels.
• Helps avoid overstabilization in pools that already use trichlor tablets or the Frog Leap system.
• Adds calcium to the water, so calcium levels should be monitored.

While dichlor is often less expensive, the cheaper option isn’t always the better option. If your pool already has high CYA levels, using dichlor can create bigger problems down the road.

The bottom line: Always check the active ingredient in your shock product and choose the one that best fits your pools needs. If you’re unsure which shock is right for your pool, give us a call at 803-203-1322 and we’ll help to find the best solution.