Product Benefits
How to Use
How to Use
Why You Should Use This Product: These calcium hypochlorite tablets provide a slow‑dissolving yet fast‑acting source of chlorine that helps sanitize pool water, kill bacteria, prevent algae, and maintain brilliant clarity. This product will not overstabilize pool water.
Before Use: Test pool water and adjust water balance as needed. Read all directions before application.
Skimmer Instructions
- Add one tablet per 10,000 gallons of pool water into an empty skimmer basket or skimmer basket insert.
- Run the pool pump a minimum of eight hours daily.
- Test water frequently and adjust the number of tablets as needed to maintain 1–4 ppm free available chlorine.
- Add new tablets as needed.
Floater Instructions
- Use a floater designed for calcium hypochlorite tablets.
- Add one tablet per 10,000 gallons of pool water into the floater and close the lid.
- Run the pool pump a minimum of eight hours daily.
- Test water frequently and adjust the number of tablets as needed to maintain 1–4 ppm free available chlorine.
- Add new tablets as needed.
Feeder Instructions
- Turn the pool pump off.
- Fill the feeder with HTH Brilliance Cal Hypo Chlorine Tablets only and close the feeder lid.
- Turn the pump on and adjust the chlorine feed rate according to the feeder manufacturer’s instructions.
- Wait 24 hours, test free available chlorine, and adjust feed rate as necessary.
Routine Chlorination
Add one tablet per 10,000 gallons of pool water every week, or as often as needed, to maintain a chlorine residual of 1–4 ppm.
Water Balance Guidelines
| Parameter | Acceptable Range |
|---|---|
| Total Alkalinity | 60–100 ppm |
| pH | 7.2–7.6 |
| Calcium Hardness | Above 200 ppm |
| Cyanuric Acid | 20–50 ppm |
| Free Available Chlorine | 1–4 ppm |
Ingredients
Ingredients
Active Ingredient:
Calcium Hypochlorite: 48.4%
Other Ingredients: 51.6%
Total: 100.0%
Safety, Storage, and Disposal
Safety
Use this product only as directed. Avoid contact with eyes, skin, and clothing, and avoid breathing dust or fumes.
Wear protective eyewear and gloves when handling, and wash hands thoroughly with soap and water after use.
Do not mix this product with other chemicals.
For complete safety information, warnings, and first aid instructions, refer to the product label.
First Aid
If the product comes into contact with eyes or skin, rinse gently with water for 15–20 minutes and seek medical advice if irritation persists.
If swallowed or inhaled, contact a poison control center or medical professional immediately.
Storage and Disposal
Keep this product dry and store it in its original, tightly closed container in a cool, well‑ventilated area away from heat or open flame.
Use entire contents, then triple rinse and dispose of the container in accordance with state and local regulations.
Do not reuse empty container.
For full storage, disposal, and emergency handling instructions, refer to the product label.
Reviews
Block Chlorine Lock with Cal Hypo
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Simplified Pool and Spa Care with HTH™ Test to Swim
Simplify pool and spa water testing with the HTH™ Test to Swim™ App. Scan your test strip, get instant results, and receive personalized pool care recommendations.
Transform Your Pool with Brilliance™
Looking for clearer pool water? Discover how HTH™ Brilliance Cal Hypo Chlorine Tablets improve water clarity and prevent chlorine lock.
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

Never mix products together

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



