How to Use GLB Supersonic Pool Shock: Complete Guide

 

GLB Supersonic is a fast-dissolving calcium hypochlorite shock treatment for pools and spas. Add 1 lb per 10,000 gallons for routine shocking or 2 lbs for heavy contamination. Dissolve in bucket, pour around perimeter, circulate 8 hours, wait until chlorine drops below 5 ppm before swimming. This guide covers complete dosing, application, safety, and troubleshooting for effective pool shocking.

What is GLB Supersonic Pool Shock?

GLB Supersonic is a premium calcium hypochlorite (cal-hypo) pool shock treatment that provides powerful oxidation and sanitization for swimming pools and spas. This fast-dissolving granular formula contains 73% available chlorine, making it one of the strongest shock treatments available for eliminating contaminants, killing bacteria, and destroying organic matter in pool water.

Key Features of GLB Supersonic

• High chlorine content: 73% available chlorine for powerful oxidation
• Fast dissolving: Granular formula dissolves quickly in water
• Multi purpose: Works for both shocking and daily sanitization
• Kills bacteria and algae: Eliminates harmful microorganisms
• Oxidizes contaminants: Breaks down organic matter and chloramines
• Safe for all surfaces: Compatible with vinyl, fiberglass, plaster, and tile
• Suitable for pools and spas: Effective in both applications
• Professional strength: Used by pool service professionals

How GLB Supersonic Works

GLB Supersonic uses calcium hypochlorite to rapidly raise free chlorine levels in your pool, providing powerful oxidation that kills bacteria, destroys algae, and breaks down organic contaminants. The high chlorine concentration quickly sanitizes water and eliminates chloramines that cause eye irritation and chlorine odor.

When to Shock Your Pool or Spa

Routine Shocking Schedule

Regular shocking is essential for maintaining water quality:

• Weekly shocking: Recommended for most pools during swim season
• Every 1 to 2 weeks for spas: Depending on usage frequency
• After heavy rain: Rainwater introduces contaminants
• After pool parties: Heavy bather load requires shocking
• When water appears dull or cloudy: Indicates organic buildup
• Strong chlorine smell: Indicates chloramines, not free chlorine
• Algae appearance: Shock immediately to kill algae
• Spring opening: Shock pool after winter closure

Signs Your Pool Needs Shocking

• Cloudy or hazy water despite proper chlorine levels
• Strong chlorine odor (indicates chloramines)
• Eye or skin irritation from swimmers
• Algae growth or green tint to water
• Combined chlorine above 0.5 ppm
• After heavy use or contamination
• Water lacks sparkle or appears dull

For severe algae problems, see how to fix green pool quickly.

Step by Step Application Guide

Step 1: Test Your Water Chemistry

Before shocking, test your pool or spa water:

• Free Chlorine: Note current level
• Combined Chlorine: Should be below 0.5 ppm
• pH: 7.2 to 7.6 (adjust if needed before shocking)
• Total Alkalinity: 80 to 120 ppm
• Calcium Hardness: 200 to 400 ppm

Proper pH is critical for shock effectiveness. Learn about how to maintain your pool's pH balance.

Step 2: Calculate Your Pool or Spa Volume

Accurate dosage depends on knowing your water volume:

Rectangular Pools:
Length (ft) × Width (ft) × Average Depth (ft) × 7.5 = Gallons

Round Pools:
Diameter (ft) × Diameter (ft) × Average Depth (ft) × 5.9 = Gallons

Spas:
Check owner's manual for exact capacity (typically 200 to 600 gallons)

Step 3: Determine GLB Supersonic Dosage

GLB Supersonic dosage guidelines:

Routine Shocking (Weekly Maintenance)

Pools: 1 lb per 10,000 gallons

• 10,000 gallon pool: 1 lb
• 15,000 gallon pool: 1.5 lbs
• 20,000 gallon pool: 2 lbs
• 25,000 gallon pool: 2.5 lbs
• 30,000 gallon pool: 3 lbs

Spas: 0.5 oz per 250 gallons

• 300 gallon spa: 0.6 oz
• 400 gallon spa: 0.8 oz
• 500 gallon spa: 1 oz

Heavy Shocking (Algae, Cloudy Water, Heavy Use)

Pools: 2 lbs per 10,000 gallons

Spas: Double the routine dose

Super Chlorination (Severe Problems)

Pools: 3 to 4 lbs per 10,000 gallons

Spas: Triple the routine dose

Step 4: Prepare GLB Supersonic Solution

Proper preparation ensures safe and effective application:

1. Fill a clean plastic bucket with pool or spa water (3 to 5 gallons)
2. Measure the correct amount of GLB Supersonic
3. Slowly add shock to water (never add water to shock)
4. Stir gently with a plastic or wooden stick until dissolved
5. Let solution sit for 1 to 2 minutes to ensure complete dissolution

Important: Always add chemicals to water, never water to chemicals. This prevents dangerous reactions and splashing.

Step 5: Add Shock to Pool or Spa

For Pools:

1. Turn on pool pump and ensure it's running
2. Pour dissolved shock solution around pool perimeter
3. Walk around pool, distributing evenly
4. Pour near return jets for better distribution
5. Brush pool surfaces after adding
6. Run pump continuously for 8 to 24 hours

Proper circulation is essential. Learn about how pool circulation supports proper maintenance.

For Spas:

1. Turn on spa jets
2. Pour dissolved shock solution evenly across spa surface
3. Run jets for 15 to 20 minutes to circulate
4. Leave cover off for 20 to 30 minutes to allow off-gassing
5. Run circulation for 8 hours minimum

Step 6: Wait Before Swimming

Allow time for chlorine levels to drop to safe levels:

• Routine shocking (1 lb per 10,000 gal): 8 to 12 hours
• Heavy shocking (2 lbs per 10,000 gal): 12 to 24 hours
• Super chlorination (3 to 4 lbs): 24 to 48 hours
• Always test chlorine before swimming: must be below 5 ppm
• Ideal swimming range: 1 to 3 ppm free chlorine

Step 7: Test and Adjust

After the waiting period:

• Test free chlorine level (should be 1 to 3 ppm)
• Test pH (should be 7.2 to 7.6)
• Test combined chlorine (should be below 0.5 ppm)
• Check water clarity
• Adjust chemistry if needed
• Pool is ready for swimming once chlorine is below 5 ppm

Safety Precautions

Handling GLB Supersonic Safely

• Always wear gloves and safety goggles when handling
• Work in well-ventilated area
• Never mix GLB Supersonic with other chemicals
• Add chemicals to water, never water to chemicals
• Keep away from children and pets
• Store in cool, dry place away from other chemicals
• Keep container tightly sealed
• Never use metal containers or utensils
• Wash hands thoroughly after handling
• Don't breathe dust or fumes

Storage Guidelines

• Store in original container with lid tightly closed
• Keep in cool, dry location (below 80°F)
• Store away from acids, bases, and other pool chemicals
• Keep away from heat sources and direct sunlight
• Don't store near flammable materials
• Check container regularly for damage or leaks
• Use within one year of opening for best results

Emergency Procedures

Skin Contact: Rinse immediately with plenty of water for 15 minutes. Remove contaminated clothing. Seek medical attention if irritation persists.

Eye Contact: Rinse immediately with water for 15 minutes, holding eyelids open. Seek immediate medical attention.

Inhalation: Move to fresh air immediately. If breathing is difficult, seek medical attention.

Ingestion: Do not induce vomiting. Drink water or milk. Seek immediate medical attention.

Shocking Schedule and Maintenance

Weekly Pool Shocking Routine

Best Time to Shock: Evening or night (sunlight degrades chlorine)

Weekly Schedule:

1. Test water chemistry (pH, alkalinity, chlorine)
2. Adjust pH to 7.2 to 7.6 if needed
3. Calculate and measure shock dosage
4. Dissolve shock in bucket of pool water
5. Add to pool with pump running
6. Run pump overnight (8 to 12 hours)
7. Test chlorine next morning before swimming

Follow a comprehensive pool cleaning checklist for beginners.

Spa Shocking Routine

Frequency: After each use or weekly minimum

Spa Shocking Steps:

1. Remove spa cover
2. Test water chemistry
3. Add shock with jets running
4. Run jets for 15 to 20 minutes
5. Leave cover off for 20 to 30 minutes
6. Test chlorine before use (must be below 5 ppm)
7. Replace cover once chlorine is safe

Seasonal Considerations

Summer (High Use):

• Shock weekly without fail
• May need to shock twice weekly during peak use
• Shock after pool parties or heavy use
• Monitor chlorine levels more frequently

See tips for cleaning your pool after a party.

Spring Opening:

• Shock pool with double dose after opening
• May need multiple shock treatments for green water
• Clean filter thoroughly before and after shocking

Fall/Winter:

• Continue weekly shocking if pool remains open
• Reduce frequency to every 2 weeks if usage is minimal
• Shock before closing pool for winter

Pro Tips for Maximum Effectiveness

Expert Tips from Pool Professionals

• Shock at night: Sunlight degrades chlorine, evening shocking is most effective
• Balance pH first: Shock works best when pH is 7.2 to 7.6
• Pre-dissolve shock: Always dissolve in bucket before adding to pool
• Run pump continuously: 8 to 24 hours circulation after shocking
• Brush after shocking: Helps distribute shock and dislodge contaminants
• Clean filter before shocking: Ensures optimal circulation and filtration
• Test before swimming: Always verify chlorine is below 5 ppm
• Don't overdose: More shock doesn't mean better results
• Use quality tools: Employ the best pool brushes
• Consider automation: Use automatic pool cleaners

Avoid Common Shocking Mistakes

• Shocking during day: Sunlight reduces effectiveness
• Not pre-dissolving: Undissolved granules can bleach surfaces
• Adding shock to skimmer: Concentrated chlorine damages equipment
• Not running pump long enough: Minimum 8 hours circulation required
• Swimming too soon: Wait until chlorine drops below 5 ppm
• Ignoring pH: High pH reduces shock effectiveness by 50% or more
• Mixing with other chemicals: Never mix shock with other products
• Using old shock: Shock loses potency over time

Maximizing Shock Performance

Water Chemistry: Maintain proper balance for optimal shock performance. High pH dramatically reduces chlorine effectiveness.

Filtration: Run pump 8 to 24 hours after shocking for proper circulation and contaminant removal.

Debris Removal: Skim, brush, and vacuum before shocking to remove organic matter that consumes chlorine.

Remove leaves and debris before shocking for best results.

Timing: Shock in evening or at night when UV degradation is minimal and pool isn't in use.

Troubleshooting Common Issues

Problem: Water Still Cloudy After Shocking

Solutions:

• Shock again with double dose
• Lower pH to 7.2 to 7.4 before shocking
• Clean or backwash filter thoroughly
• Run pump continuously for 24 to 48 hours
• Add clarifier to help filter capture particles
• May need algaecide if algae is present

See how to handle cloudy water in swimming pools and learn about how to use Leslie's Clear Aid pool clarifier.

Problem: Strong Chlorine Smell After Shocking

Cause: Chloramines (combined chlorine), not free chlorine

Solutions:

• This indicates you need MORE shock, not less
• Shock with double or triple dose to break chloramine bond
• Test combined chlorine: should be below 0.5 ppm
• Run pump with cover off to allow off-gassing
• Continue shocking until combined chlorine is eliminated

Problem: Algae Returns Quickly After Shocking

Solutions:

• Shock dosage may have been insufficient
• Add algaecide (like No Mor Problems algaecide or Pool RX algaecide)
• Brush pool surfaces vigorously daily
• Maintain proper chlorine levels (1 to 3 ppm) between shockings
• Check for high phosphates (algae food source)
• Consider adding solar pool ionizer for continuous algae prevention

For mustard algae, learn about whether solar pool ionizer is effective against mustard algae.

Problem: Bleached or Damaged Pool Surfaces

Cause: Undissolved shock granules sitting on surfaces

Prevention:

• Always pre-dissolve shock in bucket before adding
• Never add shock directly to pool
• Brush pool after adding shock to distribute evenly
• Pour shock solution while walking around pool perimeter

Learn how to clean pool tiles effectively for surface maintenance.

Problem: Calcium Buildup or Scaling

Cause: Cal-hypo shock raises calcium hardness over time

Solutions:

• Test calcium hardness monthly
• If above 400 ppm, partially drain and refill pool (25 to 50%)
• Consider alternating with non-calcium shock
• Maintain proper water balance

Learn about how to manage pool water hardness.

Frequently Asked Questions

How much GLB Supersonic do I need for my pool?

For routine shocking, use 1 lb per 10,000 gallons. For heavy shocking (algae, cloudy water), use 2 lbs per 10,000 gallons. For super chlorination, use 3 to 4 lbs per 10,000 gallons.

How long after shocking can I swim?

Wait time depends on dosage. Routine shocking: 8 to 12 hours. Heavy shocking: 12 to 24 hours. Super chlorination: 24 to 48 hours. Always test chlorine: must be below 5 ppm before swimming.

Can I use GLB Supersonic in my spa?

Yes! GLB Supersonic is ideal for spas. Use 0.5 oz per 250 gallons for routine shocking. Spas can typically be used 4 to 8 hours after shocking once chlorine drops below 5 ppm.

What's the difference between GLB Supersonic and dichlor shock?

GLB Supersonic is calcium hypochlorite (73% chlorine) that raises pH and calcium hardness. Dichlor is pH-neutral and contains stabilizer. GLB Supersonic is more powerful and cost effective for routine shocking.

Should I shock at night or during the day?

Always shock at night or evening. Sunlight degrades chlorine rapidly, reducing shock effectiveness. Evening shocking allows chlorine to work overnight without UV degradation.

Why does my pool smell like chlorine after shocking?

Strong chlorine smell indicates chloramines (combined chlorine), not free chlorine. This means you need MORE shock to break the chloramine bond, not less. Shock with double dose.

Can I add shock directly to my pool?

No. Always pre-dissolve shock in a bucket of pool water first. Adding shock directly can bleach surfaces and damage pool finishes. Never add shock to skimmer.

How often should I shock my pool?

Shock weekly during swim season for routine maintenance. Shock more frequently after heavy use, rain, or if water appears cloudy. With a solar ionizer, you may only need monthly shocking.

Will GLB Supersonic raise my calcium hardness?

Yes. Calcium hypochlorite shock adds calcium to pool water. Test calcium hardness monthly. If above 400 ppm, partially drain and refill pool.

Can I shock and add algaecide at the same time?

No. Shock first, wait 24 hours, then add algaecide. High chlorine levels from shocking will deactivate algaecide if added simultaneously.

Can I use GLB Supersonic with a saltwater pool?

Yes! GLB Supersonic works with all pool types including saltwater, chlorine, bromine, and mineral systems.

Learn about cleaning and maintaining saltwater pools.

Can I use GLB Supersonic with a solar pool ionizer?

Yes! GLB Supersonic works excellently with solar pool ionizers. Remove ionizer before shocking, shock pool as needed, wait until chlorine drops below 5 ppm, then return ionizer to pool.

Learn about how to use a solar pool ionizer after shocking your pool.

Conclusion

GLB Supersonic Pool Shock provides powerful, effective oxidation and sanitization for pools and spas. By following proper dosing guidelines, safety precautions, and shocking schedules, you can maintain crystal clear, sanitized water all season long with this professional strength calcium hypochlorite shock treatment.

Key Takeaways

• Routine shocking: 1 lb per 10,000 gallons weekly
• Heavy shocking: 2 lbs per 10,000 gallons for algae or cloudy water
• Always pre-dissolve shock in bucket before adding
• Shock at night or evening for maximum effectiveness
• Balance pH to 7.2 to 7.6 before shocking
• Run pump 8 to 24 hours after shocking
• Wait until chlorine drops below 5 ppm before swimming
• Test combined chlorine: should be below 0.5 ppm
• Monitor calcium hardness monthly (cal-hypo adds calcium)
• Remove solar ionizer before shocking, return after chlorine drops

For comprehensive pool care that reduces shocking frequency and chemical usage, consider adding a Solar Pool Ionizer which provides continuous algae and bacteria prevention between shock treatments, allowing you to shock monthly instead of weekly while maintaining superior water quality with up to 85% less chlorine usage for a healthier, more eco-friendly swimming experience.