Rx Clear Mega Shock 73% Calcium Hypochlorite - Fast Algae Control

In this review the Rx Clear Mega Shock is assessed for pool owners who need a quick, powerful treatment to clear cloudy or green water. The bottom line: this one pound granular shock delivers a strong chlorine boost and works as a sanitizer, clarifier and algicide, making it useful for routine maintenance and opening pools. It is best for users who can follow safe handling and dilution steps, and who want a fast-acting, high chlorine product rather than a milder, stabilized shock alternative.

Key Features

• Multi-purpose action: Functions as a sanitizer, clarifier, and algicide so a single treatment can tackle chlorination and algae control for clearer water.
• High available chlorine: The 73% calcium hypochlorite formula provides an extra power chlorine boost to raise free chlorine levels quickly when needed.
• Mix before application: The granular powder is intended to be dissolved in a bucket first, which helps ensure safe and even distribution when added to the pool.
• Dosage guidance: Practical dosing is provided on the packet with 1 lb per 10,000 gallons for maintenance and 2 lbs per 14,000 gallons for algae treatment or seasonal openings.
• Night application recommended: Best results when added at night and waiting 8 to 10 hours before swimming, which maximizes sanitizing and clarifying performance.

Who It's For

This product suits above ground and in ground pool owners who need a reliable, concentrated shock to treat algae outbreaks, clear cloudy water, or quickly raise chlorine levels before an event. It is also appropriate for those who prefer granular, measureable packets for targeted dosing.

It is less suitable for swimmers seeking stabilized slow-release chlorine or for people who prefer liquid or stabilized dichlor products; those users should consider alternative chlorine forms. Also note the product cannot be shipped or sold to residents of Maine, so check local availability first.

Pros & Cons

Pros

• Very effective at clearing pools and killing algae due to high chlorine content.
• Dissolves quickly when mixed and is straightforward to dose for common pool sizes.
• Multi-purpose formula reduces need for separate clarifier or algaecide in many situations.

Cons

• Strong, concentrated chemical requires careful handling and pre-dissolving before adding to the pool.
• Not available for sale or shipment to Maine, limiting access for some buyers.

Specifications

Brand	Rx Clear
Active ingredient	Calcium hypochlorite (73%)
Package size	One pound bag
Pack count	12 pack
Dosage (maintenance)	1 lb per 10,000 gallons
Dosage (algae)	2 lbs per 14,000 gallons

Our Verdict

The Rx Clear Mega Shock is a strong, cost effective choice for pool owners who need a rapid chlorine boost and reliable algae control. Its high calcium hypochlorite content and clear dosing guidance make it a practical option for seasonal openings and emergency treatments, provided users follow mixing and safety instructions.

Frequently Asked Questions

How should I apply this shock?
Pre-dissolve the granular powder in a bucket of water, then add the solution to the pool at night and wait 8 to 10 hours before swimming.

What dose should I use for routine maintenance?
Use one 1 lb bag per 10,000 gallons of pool water for regular maintenance.

Can this product remove green algae?
Yes; customers report it clears pools within hours when used at the recommended algae treatment doses of 2 lbs per 14,000 gallons.