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Multifunction vs stabilised chlorine tablets

Updated: 16.10.2026

You have seen both phrases on amazon.co.uk and they look like two grades of the same puck. They are not. Multifunction vs stabilised chlorine tablets is one chemistry choice. When the listing actually says so, multifunction is stabilised chlorine plus a clarifier and an algaecide. Stabilised chlorine is the chlorine and the cyanuric acid, and you dose the other two yourself. One Relax buyer thought they had ordered pure chlorine, which is how far a vague description can travel. Prices stay on the [chlorine tablets for pools](/hub/pool-care/chlorine-tablets-pool) comparison. The Products Compared editorial team used the kept amazon.co.uk listings and two UK retail sources for this page on 15 October 2026. It is not a lab result.

You have seen both phrases on amazon.co.uk and they look like two grades of the same puck. They are not. Multifunction vs stabilised chlorine tablets is one chemistry choice.

Our top picks

Deep Blue Deep Blue stabilised 200 g tablets

Best overall

Deep Blue Deep Blue stabilised 200 g tablets
7.3/10about £31.49
View offer
Relax Relax 5 kg multifunction tablets

Rank 2

Relax Relax 5 kg multifunction tablets
8.8/10about £26.99
View offer
Deep Blue Deep Blue 5 kg 20 g multifunction tablets

Best value

Deep Blue Deep Blue 5 kg 20 g multifunction tablets
8.4/10about £21.98
View offer
On this page
  1. 1.The two words are not a quality grade
  2. 2.Which tubs in this set say which
  3. 3.Both can raise cyanuric acid
  4. 4.When multifunction, when stabilised
  5. 5.One chemistry choice, with a condition

The two words are not a quality grade

Swimming Pool Chemicals describes stabilised tablets for a skimmer or a floater, and multifunction tablets as the similar product that also adds a flocculant and an algaecide. Do not use that shop’s prices as amazon.co.uk prices. In this set, a listing that says multifunction also says stabilised chlorine. Do not read multifunction as unstabilised. Stabilised is not weaker chlorine. It is chlorine that brings cyanuric acid with it. Multifunction is not a tested promise that the pool will stay clear. The algaecide words are an ingredient claim only on the listings that print them.

Which tubs in this set say which

Relax states chlorine, stabiliser, algaecide and clarifier, and the highlight names trichloroisocyanuric acid. Do not paint that chemical name onto the other tubs. Both Deep Blue multifunction tubs state stabilised chlorine, a clarifier and an algaecide, and they do not name the chlorine compound. ChlorineXpress is stabilised chlorine with cyanuric acid named, and it does not list a clarifier. The Deep Blue stabilised listing calls itself a pure stabilised sanitiser and tells you to dose algaecide and clarifier separately. Its title says 5 kg and the weight and the model say 1 kg. Bulla’s title says multifunction, and the bullets do not list those ingredients. Pack weight and tablet size are on the chlorine tablets buying guide.
Deep Blue Deep Blue stabilised 200 g tablets

Testsieger

Deep Blue Deep Blue stabilised 200 g tablets
7.3/10about £31.49
View offer

Both can raise cyanuric acid

If the tablet is a chlorinated isocyanurate, both kinds add cyanuric acid. UK Pool Store’s sheet puts that retailer’s ideal at about 30–50 ppm. That figure is the sheet’s ideal, not a statute, and the way down is dilution. Only Relax names trichloroisocyanuric acid, so you cannot assume every tub in this set is that compound. ChlorineXpress names cyanuric acid and does not name the chlorine chemical. The mistake is to treat multifunction as everything already in there and then add a separate stabiliser as well. The tablet has already brought cyanuric acid in. Another stabiliser does not replace a test, and it does not come back out of the water except by dilution. Once you know which puck you opened, the feeder and the cap are on how to use chlorine tablets in a pool.

When multifunction, when stabilised

Choose multifunction if you will not dose three products and the listing lists stabilised chlorine, a clarifier and an algaecide. Choose stabilised chlorine if you want to control the algaecide yourself. That is one recommendation with a condition. It is not a claim that the pool cannot go green. Bulla does not meet the condition. Neither choice picks 20 g over 200 g. Who each listing suits is on best chlorine tablets for pools. You still test either way.

One chemistry choice, with a condition

Multifunction is the fit when the bullets list stabilised chlorine, a clarifier and an algaecide, and you will not buy three bottles. Stabilised chlorine is the fit when you want the algaecide in your own hands. Neither word is a higher grade, and neither word picks 20 g or 200 g. If the title says multifunction and the bullets are silent, it is not the same buy. A qualifying purchase can earn a commission at no extra cost to you.

Common questions

What is actually in a multifunction tablet?
Stabilised chlorine, plus a clarifier and an algaecide, when the listing says so. Swimming Pool Chemicals uses flocculant and algaecide for the same idea. Relax states those extras and names trichloroisocyanuric acid. Both Deep Blue multifunction tubs state the three jobs without naming the chlorine compound. If the bullets are silent, the title is not enough. Bulla is that case. Multifunction here is still stabilised, not unstabilised.
What is missing from a stabilised tablet?
The clarifier and the algaecide, which you dose yourself. ChlorineXpress names cyanuric acid, lists no clarifier, and ties algae prevention to chlorine and pH. Deep Blue’s stabilised listing says to dose those two separately, unlike multifunction. Cyanuric acid is the part that makes the tablet stabilised. The chlorine compound is not named on either of those two listings.
Do both kinds add cyanuric acid?
They can, when they are chlorinated isocyanurates. UK Pool Store’s sheet puts a retailer ideal at about 30–50 ppm and lowers it by dilution. That figure is not a statute. Only Relax names trichloroisocyanuric acid. Do not copy that name onto ChlorineXpress. Extra stabiliser on top of either kind is how the level climbs. The tablet does not remove what it added.
Will multifunction tablets stop the pool going green on their own?
Not on the evidence in this set. An algaecide line is an ingredient claim, not a test, and not a reason to skip chlorine and pH. ChlorineXpress, which is not multifunction, already ties algae prevention to those two readings. Bulla’s line about killing algae is not an ingredient list. If the water is green, find the reading before you trust the word on the tub.
Why does Bulla say multifunction if the bullets do not list algaecide?
The title says multifunction and the bullets do not list stabiliser, algaecide or clarifier. The benefits field says it kills algae. That is a claim line, not a contents list. Treat it as a 1 inch kit with a floater, not as the same buy as Relax. If you need the three ingredients, buy a listing that prints them.
Can I use stabilised tablets and a separate algaecide?
Yes, if you want to control the algaecide yourself. That is what the Deep Blue stabilised listing tells you to do. ChlorineXpress is the other stabilised tub, with cyanuric acid named and no clarifier stated. You still test, and you do not add extra stabiliser because the algaecide is in another bottle. Yes does not settle that Deep Blue tub as 5 kg.

Related pages

Algaecide or chlorine tablets

Chlorine tablets pool

Best chlorine tablets for pools: who each tub fits

Chlorine tablets buying guide: chemistry, size, weight

How to use chlorine tablets in a pool, step by step

Chlorine tablets for a small pool or paddling pool

Sources

Public UK sources listed in the research digest. Listing prices, stars, and review counts are from the amazon.co.uk capture dated 15 October 2026, not a live re-check.

  1. HSE — Swimming pool safety management (retrieved 15 October 2026)
  2. HSE SR9 — Safe use of pool biocides (retrieved 15 October 2026)
  3. HSE — Biocides regulations (retrieved 15 October 2026)
  4. HSE — GB CLP classification and labelling (retrieved 15 October 2026)
  5. PWTAG Code of Practice (retrieved 15 October 2026)
  6. PWTAG TN68 — Handling and storage of pool chemicals (retrieved 15 October 2026)
  7. UK Pool Store — What is cyanuric acid (retrieved 15 October 2026)
  8. Swimming Pool Chemicals — Chlorine tablets (retrieved 15 October 2026)