Pool & spa
Clearwater Bromine Tablets dupe
Why pay around £24.00 for Clearwater? The bulk active is BCDMH bromine tablets 20 g — 54% less per working litre than a typical shelf pack.
From the retail pack to the active and the mix
1 · Retail
Clearwater Bromine Tablets
1 kg tub · £24.00 typical snapshot
Tablet binder
2 · Active
BCDMH (1-bromo-3-chloro-5,5-dimethylhydantoin)
96% on the label
16079-88-2C5H6BrClN2O2
Bulk BCDMH bromine tablets 20 g
3 · Mix
1–2 tablets in a floater; maintain 3–5 ppm bromine
£0.01 per working litre · 54% less than the shelf pack
- Active
- BCDMH (1-bromo-3-chloro-5,5-dimethylhydantoin)
- CAS
- 16079-88-2
- Dupe
- BCDMH bromine tablets 20 g
- Saving
- 54% / L
Saving is per litre of working-strength mix versus a typical pack price, not versus the DIY kit total. Shop prices move — always check the listing.
Label teardown
What the pack promises versus what the label chemistry actually is.
The marketing claim
“Spa sanitiser that works better than chlorine in hot water”
The chemical reality
Spa bromine tablets are BCDMH. The 1 kg tub is the same 20 g pucks sold in 5 kg tubs to holiday-park plant rooms. You still need a floater and a test kit.
Active vs filler
96% BCDMH (1-bromo-3-chloro-5,5-dimethylhydantoin) · 4% carrier / filler — Tablet binder
- Typical retail
- £24.00
- 1 kg tub
- Estimated active cost
- £11.00
- Scaled from bulk £55.00 / 5 kg
- Indicative markup
- 2.2×
- Snapshot maths, not a live shop price
The Marketing Claim & The Catch
A 1 kg tub pack of Clearwater Bromine Tablets typically retails around £24.00 in pool & spa. That is a UK shelf-price snapshot for the maths on this page — not a live shop quote or a manufacturer RRP. Listings, sizes and deals move. The marketing line is that you are buying a finished lifestyle product, not a weighed chemical.
On the pack: Spa sanitiser that works better than chlorine in hot water; and Slow-dissolving tablets for a floater.
The catch: Spa bromine tablets are BCDMH. The 1 kg tub is the same 20 g pucks sold in 5 kg tubs to holiday-park plant rooms. You still need a floater and a test kit.
- “Spa sanitiser that works better than chlorine in hot water”
- “Slow-dissolving tablets for a floater”
Proprietary Blend & Dosage Breakdown
The labelled active is BCDMH (1-bromo-3-chloro-5,5-dimethylhydantoin) at 96%. Everything else in the pack is tablet binder.
Even when the pack is sold as “pure” or ready-to-use, the dose that actually does the work is BCDMH (1-bromo-3-chloro-5,5-dimethylhydantoin). The rest is how they get it into a bottle you will pick up.
Branded working strength is whatever comes out of the bottle. The bulk alternative is 96% BCDMH bromine tablets 20 g, mixed to 1–2 tablets in a floater; maintain 3–5 ppm bromine.
- Labelled active
- BCDMH (1-bromo-3-chloro-5,5-dimethylhydantoin)
- 96%
- Carrier
- Tablet binder
- Retail pack
- 1 kg tub · £24.00
The Active Chemical Alternative (Dupe Stack)
The dupe stack is BCDMH bromine tablets 20 g at 96% bulk. Indexed as CAS 16079-88-2, formula C5H6BrClN2O2. Buy it as 5 kg for around £55.00 from Amazon UK.
Working strength: 1–2 tablets in a floater; maintain 3–5 ppm bromine. Indicative cost £0.01 per diluted litre — 54% below a typical branded pack on a per-litre basis, before you reuse leftover bulk.
Follow the mixing method and the supplier SDS. Wear the listed PPE. Do not mix incompatible oxidisers, acids or ammonia.
- Gloves and goggles. Do not mix with cal-hypo or acid in a bucket. Tablets go in a floating dispenser, not loose on the acrylic.
- Typical spa start is one or two 20 g tablets; then test. Target 3–5 ppm bromine in hot water.
- 5 kg is five 1 kg tubs. Store dry. This is a sanitiser, not a fragrance.
Dilution recipe
1,500 L pool / spa volume
Working strength 1–2 tablets in a floater; maintain 3–5 ppm bromine. Educational estimate from the listed ratio — check the SDS before you mix.
Chemical
19.5 grams
BCDMH bromine tablets 20 g
Water
1,500 litres
Carrier / diluent
0% concentrate · 100% water by working volume (solids are dissolved into the water share).
Required PPE
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Side-by-Side Price & Potency Comparison
Head-to-head comparison
| Measure | Retail brandedClearwater | Raw active dupeDupeStack |
|---|---|---|
| Product | Bromine TabletsAmazon UK search — listing, not a confirmed seller | BCDMH bromine tablets 20 g |
| Pack / unit | 1 kg tub · £24.00 | 5 kg · £55.00 |
| Active | BCDMH (1-bromo-3-chloro-5,5-dimethylhydantoin) at 96%Carrier: Tablet binder | 96% bulkC5H6BrClN2O2 |
| CAS number | Not disclosed on pack | 16079-88-2 |
| Working strength | Ready-to-use pack | Dilute 1–2 tablets in a floater; maintain 3–5 ppm bromine |
| Cost per litre | £24.00 / pack | £0.01 / L mixed from bulk |
| Headline saving | Baseline | 54% cheaper |
| COSHH / PPE | Follow the branded SDS | Gloves. Chemical-resistant gloves (nitrile or neoprene)Eye protection. Indirect-vent splash goggles — not ordinary spectacles |
Active ingredient and cheaper alternative — FAQ
What is the active ingredient in Clearwater?
Clearwater Bromine Tablets is labelled as BCDMH (1-bromo-3-chloro-5,5-dimethylhydantoin) at 96%. The carrier is Tablet binder. Pack size: 1 kg tub. The bulk equivalent we index is BCDMH bromine tablets 20 g (CAS 16079-88-2).
Is BCDMH bromine tablets 20 g safe on the intended surface?
Used at the listed working strength (1–2 tablets in a floater; maintain 3–5 ppm bromine), the dupe is the same chemistry as the branded pack for pool and spa water once dosed from a test kit. That is not a blanket all-clear: read the supplier SDS, wear the listed PPE, keep acids away from hypochlorite, and follow UK HSE/COSHH rules. Wellness teardowns are supplements, not medicines.
Is there a cheaper alternative to Clearwater Bromine Tablets?
Yes. The bulk equivalent is BCDMH bromine tablets 20 g (CAS 16079-88-2). Indicative saving 54% per working litre versus a pack that typically retails around £24.00. Working strength: 1–2 tablets in a floater; maintain 3–5 ppm bromine. Live shop prices move.
How do you mix the Bromine Tablets dupe stack?
Gloves and goggles. Do not mix with cal-hypo or acid in a bucket. Tablets go in a floating dispenser, not loose on the acrylic. Typical spa start is one or two 20 g tablets; then test. Target 3–5 ppm bromine in hot water. 5 kg is five 1 kg tubs. Store dry. This is a sanitiser, not a fragrance.
DupeStack provides chemical concentration data and educational mixing guides only. Wellness pages compare food supplements, not medicines or prescribed treatments. Always review the supplier Safety Data Sheet (SDS) and comply with UK Health and Safety Executive (HSE) and COSHH regulations when handling concentrated substances. Mixing and storage are at your own risk. Some links are affiliate advertisements (Amazon Associates, eBay Partner Network, and Awin when those programmes are live). Commissions do not change listed concentrations or calculator output.
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Indicative DIY stack