Household cleaning
HG Limescale Remover Foam Spray Super Powerful dupe
Why pay around £6.50 for HG? The bulk active is Phosphoric acid 81% (food / technical) diluted to ~30% — 64% less per working litre than a typical shelf pack.
From the retail pack to the active and the mix
1 · Retail
HG Limescale Remover Foam Spray Super Powerful
500 millilitres · £6.50 typical snapshot
Water, foam surfactant and a little oxalic
2 · Active
Phosphoric acid
30% on the label
7664-38-2H3PO4
Bulk Phosphoric acid 81% (food / technical) diluted to ~30%
3 · Mix
1:1.7 (1 part 81% + 1.7 parts water → ~30%)
£4.63 per working litre · 64% less than the shelf pack
- Active
- Phosphoric acid
- CAS
- 7664-38-2
- Dupe
- Phosphoric acid 81% (food / technical) diluted to ~30%
- Saving
- 64% / 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
“Three times stronger — persistent scale on showers and taps”
The chemical reality
HG Super Powerful foam is phosphoric acid at about 30% w/w — a bathroom descale, not Jenolite rust gel and not citric kettle sachets. Dilute 81% food-grade phosphoric 1:1.7 to the same band. Keep it off marble and never mix it with bleach.
Active vs filler
30% Phosphoric acid · 70% carrier / filler — Water, foam surfactant and a little oxalic
- Typical retail
- £6.50
- 500 millilitres
- Estimated active cost
- £2.31
- Scaled from bulk £12.50 / 1 litre
- Indicative markup
- 2.8×
- Snapshot maths, not a live shop price
The Marketing Claim & The Catch
A 500 millilitres pack of HG Limescale Remover Foam Spray Super Powerful typically retails around £6.50 in household cleaning. 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: Three times stronger — persistent scale on showers and taps; Rich foam that clings on vertical surfaces; and Does not affect chrome, glaze or grout.
The catch: HG Super Powerful foam is phosphoric acid at about 30% w/w — a bathroom descale, not Jenolite rust gel and not citric kettle sachets. Dilute 81% food-grade phosphoric 1:1.7 to the same band. Keep it off marble and never mix it with bleach.
- “Three times stronger — persistent scale on showers and taps”
- “Rich foam that clings on vertical surfaces”
- “Does not affect chrome, glaze or grout”
Proprietary Blend & Dosage Breakdown
The labelled active is Phosphoric acid at 30%. Everything else in the pack is water, foam surfactant and a little oxalic.
At 30% active, most of what you pay for is carrier and packaging. The brand is selling convenience, fragrance and a label — not a uniquely potent molecule.
Branded working strength is whatever comes out of the bottle. The bulk alternative is 81% Phosphoric acid 81% (food / technical) diluted to ~30%, mixed to 1:1.7 (1 part 81% + 1.7 parts water → ~30%).
- Labelled active
- Phosphoric acid
- 30%
- Carrier
- Water, foam surfactant and a little oxalic
- Retail pack
- 500 millilitres · £6.50
The Active Chemical Alternative (Dupe Stack)
The dupe stack is Phosphoric acid 81% (food / technical) diluted to ~30% at 81% bulk. Indexed as CAS 7664-38-2, formula H3PO4. Buy it as 1 litre for around £12.50 from Amazon UK.
Working strength: 1:1.7 (1 part 81% + 1.7 parts water → ~30%). Indicative cost £4.63 per diluted litre — 64% 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.
- Causes burns. Splash goggles, household gloves, ventilation. Always add acid to water. Never mix with bleach — chlorine gas risk.
- Mix 1 part 81% phosphoric acid with 1.7 parts water (370 ml acid made up to 1 litre) for a ~30% liquor matching the foam spray’s acid band — without the foam surfactant.
- Apply sparingly to wet limescale on ceramic, chrome and glass. Dwell a few minutes, wipe, rinse. Keep off marble, limestone, enamel you care about, and aluminium.
- 1 litre of 81% makes about 2.7 litres of 30% liquor — roughly five 500 ml trigger bottles.
- This is a bathroom descale, not a rust converter (see Jenolite) and not a kettle sachet (citric or sulfamic). Store in a labelled HDPE bottle, locked away from children.
Dilution recipe
0.5 L working batch
Working strength 1:1.7 (1 part 81% + 1.7 parts water → ~30%). Educational estimate from the listed ratio — check the SDS before you mix.
Chemical
185 millilitres
Phosphoric acid 81% (food / technical) diluted to ~30%
Water
0.31 litres
Carrier / diluent
38% concentrate · 62% water by working volume (solids are dissolved into the water share).
Required PPE
Loading calculator…
Side-by-Side Price & Potency Comparison
Head-to-head comparison
| Measure | Retail brandedHG | Raw active dupeDupeStack |
|---|---|---|
| Product | Limescale Remover Foam Spray Super PowerfulAmazon UK search — listing, not a confirmed seller | Phosphoric acid 81% (food / technical) diluted to ~30% |
| Pack / unit | 500 millilitres · £6.50 | 1 litre · £12.50 |
| Active | Phosphoric acid at 30%Carrier: Water, foam surfactant and a little oxalic | 81% bulkH3PO4 |
| CAS number | Not disclosed on pack | 7664-38-2 |
| Working strength | Ready-to-use pack | Dilute 1:1.7 (1 part 81% + 1.7 parts water → ~30%) |
| Cost per litre | £13.00 / L typical pack | £4.63 / L mixed from bulk |
| Headline saving | Baseline | 64% cheaper |
| COSHH / PPE | Follow the branded SDS | Gloves. Chemical-resistant gloves (nitrile or neoprene)Eye protection. Indirect-vent splash goggles — not ordinary spectaclesVentilation. Use outdoors or with mechanical extractionAcid-resistant PPE. Apron and gloves rated for corrosive liquids |
Active ingredient and cheaper alternative — FAQ
Is this the same as Jenolite rust remover?
Same molecule (phosphoric acid, CAS 7664-38-2), different job and strength. Jenolite is a ~25% rust-conversion gel for steel. This HG foam is a ~30% bathroom limescale spray. Do not use rust gel on taps, and do not treat this as a rust converter.
Is this the same as Cillit Bang limescale spray?
No. Cillit Bang is typically citric and/or sulfamic in a 750 ml trigger. HG Super Powerful is phosphoric — a stronger mineral acid. Different SDS, different surfaces. Never mix either with bleach.
How do you mix the Limescale Remover Foam Spray Super Powerful dupe stack?
Causes burns. Splash goggles, household gloves, ventilation. Always add acid to water. Never mix with bleach — chlorine gas risk. Mix 1 part 81% phosphoric acid with 1.7 parts water (370 ml acid made up to 1 litre) for a ~30% liquor matching the foam spray’s acid band — without the foam surfactant. Apply sparingly to wet limescale on ceramic, chrome and glass. Dwell a few minutes, wipe, rinse. Keep off marble, limestone, enamel you care about, and aluminium. 1 litre of 81% makes about 2.7 litres of 30% liquor — roughly five 500 ml trigger bottles. This is a bathroom descale, not a rust converter (see Jenolite) and not a kettle sachet (citric or sulfamic). Store in a labelled HDPE bottle, locked away from children.
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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- Retail pack
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£22.50Save 64% / L
Indicative DIY stack