HTH™ Pool Care Green to Blue Advanced

2-Step Pool Shock & Flocculant

HTH™ Pool Care Green to Blue Advanced

2-Step Pool Shock & Flocculant

HTH™ Pool Care Green to Blue Advanced Shock is a 2 step green to blue pool recovery system designed to correct severe green water caused by algae blooms. 

  • Advanced I delivers a powerful calcium hypochlorite (cal hypo) shock that kills algae and bacteria without adding cyanuric acid (CYA), helping avoid chlorine lock.
  • Advanced II is a pool flocculant that binds to dead algae and fine debris, causing it to sink to the pool floor for direct vacuuming to waste. 
  • Used together and with the proper pool equipment, this system can turn pool from green to blue in as little as 24 hours. 
  • It is safe for vinyl‑lined pools when used as directed and is especially effective after storms, heavy algae outbreaks, or periods of high pool use.

You're All Clear with HTH™!

Product Benefits

Green Pool Fix Fast

This 2 step system is designed to correct severe green pool water caused by algae. When used as directed and with the proper equipment, it can help restore clear, blue water in as little as 24 hours.

Cal Hypo Pool Shock without Chlorine Lock

Advanced I uses a calcium hypochlorite shock to kill algae and bacteria without CYA, helping prevent overstabilization and chlorine lock.

Pool Flocculant Binds Debris For Easy Vacuuming

Advanced II is a pool flocculant that binds dead algae and fine particles, causing them to sink to the pool floor so they can be vacuumed directly to waste instead of clogging the filter.

Pool Turned Green Overnight?

Ideal for severe algae blooms, post‑storm cleanup, or heavily neglected pools. Safe for vinyl‑lined pools when used as directed and compatible with pool systems that can vacuum to waste.

How to Use

Before You Start

This system requires specific pool equipment to work correctly. Do not begin unless you have the following:

  • A filter system with a multiport valve that includes Recirculate (or Bypass) and Waste settings
  • A manual pool vacuum that connects directly to the filter system
  • The ability to vacuum to waste

This product will not work with robotic cleaners or vacuums that collect debris in mesh or debris bags.

How to Use

Follow each step in order. Allow products to fully dissolve and work before moving to the next step.

Step 1: Add Advanced I

Set the filter to its normal filtration setting.

Add the entire contents of Green to Blue Advanced I directly to the pool.

Allow the product to fully dissolve and circulate through the water.

Step 2: Add Advanced II

Once Advanced I is fully dispersed, switch the filter setting to Recirculate or Bypass.

Add the entire contents of Green to Blue Advanced II through the skimmer.

This product may appear brown or orange in color. This is normal.

Step 3: Circulate and Let Settle

Leave the filter running on Recirculate for 1 hour.

Turn the pump off and allow the water to sit overnight.

The flocculant will bind to dead algae and settle on the pool floor.

Step 4: Vacuum to Waste

Once debris has settled (up to 24 hours), set the filter to Waste.

Carefully vacuum the sediment directly out of the pool.

Do not vacuum through the filter.

After vacuuming, return the filter to its normal filtration setting.

Helpful Tips

  • If particles are slow to settle, lightly mist the pool surface with a garden hose to break surface tension.
  • If the pool remains green, repeat the shock step before allowing the flocculant to settle again.
  • Severe algae blooms may require more than one shock treatment.
  • Always test water chemistry after treatment and adjust as needed.

Ingredients

What’s Included

  • HTH Pool Care Green to Blue Advanced I (Cal Hypo shock)
  • HTH Pool Care Green to Blue Advanced II (flocculant)

Green to Blue Advanced I

Active Ingredient:

Calcium Hypochlorite: 56.44%

Other Ingredients: 43.56%

Total: 100.00%

Green to Blue Advanced II

Ingredients:

Contains polyaluminum chloride.

Safety, Storage, and Disposal

Safety & Label Guidance

This kit contains multiple pool care products. Always read and follow the directions, safety precautions, and first aid instructions on each individual product label.

Do not mix products together and do not use in floaters or feeders.

Keep all products stored in a cool, dry, well‑ventilated area and out of reach of children.

Green to Blue Advanced I

Active Ingredient:

Calcium Hypochlorite: 56.44%

Other Ingredients: 43.56%

Total: 100.00%

Green to Blue Advanced II

Ingredients:

Contains polyaluminum chloride.

Frequently Asked Questions

  • What does HTH™ Green to Blue Advanced do, and how does it work?

    HTH™ Green to Blue Advanced is a two-step treatment system designed to restore a green, algae-filled pool to clear blue water. Step 1 is a cal hypo shock that kills algae. Step 2 is a flocculant that gathers dead algae and debris so they can be vacuumed to waste. When used as directed, the system typically restores water clarity within 24 hours.

  • How do I use HTH™ Green to Blue Advanced?

    Step 1: Add HTH™ Green to Blue Advanced I, a cal hypo shock, directly to the pool with the pump running. Step 2: Move the multiport valve to "recirculate" and add HTH™ Green to Blue Advanced II, a flocculant, to the skimmer. Circulate for one hour, then turn off the pump. The next day, vacuum the sediment to waste. IMPORTANT: YOU MUST HAVE A MULTIPORT VALVE THAT CAN VACUUM TO WASTE TO USE THIS PRODUCT.

  • How long does HTH™ Green to Blue Advanced take to clear a pool?

    Most pools clear within 24 hours when HTH™ Green to Blue Advanced is used as directed. Pools with severe algae blooms may take longer and require a second treatment. Brushing the pool surfaces will help speed up the process.

  • My pool is still green after using HTH™ Green to Blue Advanced—what should I do?

    If the pool is still green after 24 hours, a second dose of HTH™ Green to Blue Advanced I may be needed. After adding it to the pool, wait another day and proceed to vacuum the sediment to waste. You must have a multiport valve that can vacuum to waste to use this product.

  • Can HTH™ Green to Blue Advanced be used in a saltwater pool?

    Yes. HTH™ Green to Blue Advanced can be used in saltwater pools. Salt chlorine generators often struggle to keep up with the demand of a heavy algae bloom, making a direct shock and flocculant treatment necessary. Follow the standard HTH™ Green to Blue Advanced instructions—the system is compatible with saltwater pool chemistry and will not harm the generator cell.

  • Do I need to add other chemicals alongside HTH™ Green to Blue Advanced?

    Before starting HTH™ Green to Blue Advanced, ensure the pH is between 7.2–7.6—high pH significantly reduces the effectiveness of the shock step. The kit includes a cal hypo shock and a strong flocculant. Once the treatment is complete and the pool is clear, resume your normal maintenance routine with weekly chlorine tabs, testing, and algaecide. You may need a second treatment for very severe algae blooms. IMPORTANT: YOU MUST HAVE A MULTIPORT VALVE THAT CAN VACUUM TO WASTE TO USE THIS PRODUCT.

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Quick Pool Tips

  • Always read product label directions prior to using and use only as directed

  • Always add chemicals to pool water, never the other way around

  • Never add chemicals to pool water when people are in the pool

  • Warning symbol with a triangle and exclamation mark on a blue background

    Never mix products together

  • Always store pool products in a cool, dry location and out of direct sunlight