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Member's Mark 3" Chlorinating Tablets, 40 lbs.

|530 ratings
Item # 990400822
Current price is Now $139.98
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Highlights

  • Weight: 40 lb pail
  • Tablet Size: 3 in
  • Item Form: Tablets
  • Pool Type: Chlorine-treated pools/spas
  • Wrapped: Individually wrapped
  • Dosage: 1/10,000 gal

  • 40 lbs. pail of 3" chlorinating tablets for chlorine-treated pools and spas
  • Helps kill bacteria and control algae for a cleaner, more hygienic pool
  • Consistent chlorine release to maintain ongoing sanitizing performance
  • Slow and steady dissolving tablets for long-lasting chlorine delivery
  • Easy to use: pre-measured tablets drop in and dissolve without complex measuring
  • Individually wrapped tablets help maintain potency until you are ready to use them
  • Use 1 tablet per 10,000 gallons every 5–7 days (after balancing and stabilizing pH)
  • Store in a cool, dry, ventilated area; use gloves and wash hands after handling
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member's mark 3" chlorinating tablets, 40 lbs. white 40 lb pail with yellow snap-on lid, centered front-facing view showing blue label with Member's Mark logo and bold 'Chlorinating Tablets' and marked '3" tablets' and net weight 40 lbs; suitable for pool maintenance and spa sanitization, often paired with floating dispensers for steady chlorine release.
Member's Mark 3" Chlorinating Tablets, 40 lbs.
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About this item

Product details

Member's Mark 3" Chlorinating Tablets deliver slow, steady chlorine release to help keep chlorine-treated pools and spas clean, sanitized, and algae-controlled with simple, pre-measured dosing.

Consistent chlorine release for cleaner water

These 3" chlorinating tablets release a consistent flow of chlorine to help kill bacteria and control algae, supporting a hygienic swimming or soaking environment. The slow-dissolving format helps maintain sanitization over time without complex measurements.

Individually wrapped tablets for maintained potency

Each tablet is individually wrapped to help maintain potency until use. This packaging supports convenient handling and predictable dosing—use the number of tablets needed for your water volume.

Simple weekly dosing with pre-measured tablets

  • For routine care, add 1 tablet per 10,000 gallons of pool or spa water every 5–7 days or as needed, depending on weather and usage conditions.
  • For best results, add tablets after stabilizing and balancing your pool’s pH.
  • The tablets dissolve on their own and are described as eliminating bacteria and controlling algae without leaving any residue.
  • These tablets are described as resistant to sunlight degradation for prolonged sanitization over time.

Important handling notes

  • Do not mix these tablets with other chemicals; add the tablets to the pool or spa as directed and allow them to dissolve on their own.
  • These tablets can help reduce pH levels, so maintaining balanced water chemistry is recommended.
  • The tablets are described as pure and containing no fillers.

Safe handling and storage

Wear gloves when handling the tablets and wash hands thoroughly afterward. Store the 40 lbs. pail in a cool, dry, ventilated area away from moisture, and avoid placing the pail on wet floors to help maintain product integrity.

Frequently Asked Questions

What size and quantity comes in Member's Mark 3" Chlorinating Tablets?

3-inch chlorinating tablets in a 40 lb pail.

What do these chlorinating tablets do for my pool or spa?

They release a consistent flow of chlorine to kill bacteria and help control algae for ongoing sanitizing.

How often should I add Member's Mark 3" chlorine tablets?

Add a tablet every 5–7 days, depending on weather and usage conditions.

How much should I use per dose?

Use 1 tablet per 10,000 gallons of water every 5–7 days or as needed.

Do I need to balance my pool water before using these tablets?

Yes—add tablets after stabilizing and balancing your pool’s pH.

How does the slow, steady chlorine release help with maintenance?

Slow-dissolving tablets provide steady chlorine over time, helping maintain more consistent sanitizing between additions.

Why are the tablets individually wrapped?

Individual wrapping helps maintain tablet potency.

Are these tablets resistant to sunlight degradation?

Yes. They’re described as resistant to sunlight degradation for prolonged sanitization over time.

Do these tablets contain fillers or leave residue?

They’re described as pure with no fillers and formulated to eliminate bacteria and control algae without leaving residue.

How should I handle and store these chlorine tablets?

Wear gloves when handling and wash hands afterward. Store the pail in a cool, dry, ventilated area away from moisture, and avoid placing it on wet floors.

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Specifications

  • Size: 3" tablets
  • Weight: 40 lbs pail
  • Packaging: Pail; tablets are individually wrapped to help maintain potency
  • Application: Suitable for chlorine-treated pools and spas
  • Chlorine Release: Slow and steady release
  • Performance: Helps curb bacteria growth and control algae; effective sanitization and bacterial control
  • Dosing Guidance: 1 tablet per 10,000 gallons every 5–7 days (depending on weather and usage conditions)
  • Use & Handling: Drop-in tablets; no messy chemicals or complex measurements; use gloves when handling and wash hands thoroughly afterward; avoid mixing tablets
  • Storage: Store in a cool, dry, ventilated area away from moisture; avoid placing the pail on wet floors
  • Notes: Use after stabilizing and balancing pool pH; tablets can help reduce pH levels; contains no fillers (per product description); described as resistant to sunlight degradation
  • Features: Kills bacteria and controls algae; slow and steady chlorine release; easy-to-use with no complex measurements; suitable for chlorine-treated pools and spas

Member ratings & reviews

4.6 out of 5 stars
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530 ratings262 reviews
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Showing 1-3 of 262 reviews

Mar 27, 2026
Reviewer name: Mas
5 out of 5 stars
5 out of 5 stars review

Verified Purchase

Chlorine tablets low cost

Love the tablets and stability of the chlorine mixture. They keep my pool nice and clear for a low cost.

Helpful?6RV9RIFQCOD015430857894
Mar 18, 2026
Reviewer name: Maria H
5 out of 5 stars
5 out of 5 stars review

Verified Purchase

Chlorine tabs

Chlorine tabs are the perfect size for chlorinators. Although the cost is higher than a few years ago, it's still affordable.

Helpful?6RV9RIFQCOD015430857894
May 18, 2026
Reviewer name: MGHAWK
5 out of 5 stars
5 out of 5 stars review

Verified Purchase

Good chlorine at a good price

Because pools are expensive to build, own and maintain I always look for who has what I need on sale or for the best price. Sam’s has been my go to place for chlorine for 6 years now

Helpful?6RV9RIFQCOD015430857894