Pool Chlorine Tablets 200g - Multifunctional Stabilised

Slow-dissolving 200 g stabilised chlorine tablets for swimming pools. Drop into the skimmer or a feeder to hold 1-3 ppm free chlorine for 5-7 days per dose. Built-in cyanuric acid keeps chlorine UV-stable through the swim season.

• Holds free chlorine at 1-3 ppm for 5-7 days per dose.
• Built-in cyanuric acid stabilises chlorine against UV burn-off.
• Dissolves slowly in skimmer baskets or floating feeders.
• Cuts daily dosing labour to a weekly top-up routine.
• Pairs with pH Minus to offset the acidic drift TCCA causes over time.

Sizes and prices

• 5kg: £39.00
• 10kg: £79.00
• 25kg: £199.00

When you need it

• You want a weekly maintenance regime, not daily granule dosing.
• Free chlorine reading is below 1 ppm.
• The pool runs through summer and needs UV-stable chlorine.
• You need an automatic feed via skimmer or floating dispenser.
• Cyanuric acid is below 30 ppm and you want to top it up while sanitising.

How to use

1. Confirm pH 7.2-7.6, total alkalinity 80-120 ppm and CYA 30-50 ppm.
2. Place tablets in the skimmer basket, an automatic feeder or a floating dispenser.
3. Use 1 tablet (200 g) per 30-50 m³ of pool water as a starting dose.
4. Run filtration for at least 8 hours after loading new tablets.
5. Test free chlorine after 24 hours; aim for 1-3 ppm.
6. Replenish weekly; never broadcast tablets directly into the pool.

Dosing guide

TCCA is acidic; expect pH and alkalinity to drift down over weeks. Test pH and TA weekly and dose pH Plus or Alkalinity Increaser as required. Avoid using in indoor pools where CYA is undesirable.

• For 20 m³ (small garden pool), add 1 tablet weekly to reach 1-3 ppm chlorine.
• For 40 m³ (mid-size pool), add 1-2 tablets weekly to reach 1-3 ppm chlorine.
• For 60 m³ (large garden pool), add 2 tablets weekly to reach 1-3 ppm chlorine.
• For 100 m³ (commercial small), add 3-4 tablets weekly to reach 1-3 ppm chlorine.
• For Heavy bather load, add Add 1 extra tablet plus a weekly shock to reach Maintain 2-3 ppm.

How it works

Trichloroisocyanuric acid (TCCA) compressed into 200 g slow-release tablets at typically 90% available chlorine, with cyanuric acid built in as a UV stabiliser.

TCCA hydrolyses in water to release hypochlorous acid (HOCl), the active sanitiser. The cyanurate fraction binds spare chlorine into a UV-stable reservoir so the active fraction is replenished as it is consumed by sun and bathers.

Without stabilisation, sunlight destroys 90% of free chlorine in two hours. TCCA is the standard outdoor pool sanitiser because the built-in stabiliser keeps chlorine present long enough to actually do its job.

Frequently asked questions

How long does one tablet last?

Around 5-7 days in a typical 30-50 m³ pool with normal bather load and circulation.

Where do I put the tablets?

In the skimmer basket, an automatic feeder or a floating dispenser, never broadcast loose into the pool.

How many tablets for my pool?

Roughly one 200 g tablet per 30-50 m³ per week, adjusted by testing weekly.

How long does a 5 kg pack last?

25 tablets, around 5-6 months of weekly dosing for a 40 m³ family pool.

Can I use these in a hot tub?

No. Hot tubs need 20 g tablets and a sanitiser stable above 38 C; use Bromine Tablets or Chlorine Mini Tablets instead.

Are they safe for vinyl liners?

Yes when fed through a skimmer or feeder; never let a tablet sit on the liner directly or it will bleach the vinyl.

What is the active ingredient?

Trichloroisocyanuric acid (TCCA) at 90% available chlorine, with built-in cyanuric acid stabiliser.

Why does my pH keep dropping?

TCCA is mildly acidic. Expect to dose pH Plus and alkalinity buffer alongside the tablets to hold balance.

What CYA level should I aim for?

30-50 ppm for outdoor pools. Above 80 ppm chlorine becomes locked up and you need to drain down.

Chlorine reads zero?

Replace tablets, check skimmer flow and shock with cal-hypo as a fast top-up.

CYA too high?

Drain 25-50% of pool water and refill; pause TCCA for 4 weeks.

Tablet not dissolving?

Open feeder ports, check temperature, switch to granules if water is cold.

TCCA vs cal-hypo?

TCCA is slow, stabilised, mildly acidic; cal-hypo is fast, unstabilised and pH-raising. Use TCCA for routine dosing, cal-hypo for shocks.

TCCA vs liquid chlorine?

Tablets are storable and self-feeding; liquid chlorine needs metering pumps and decays in storage. Tablets win for domestic pools.