mains water in

treated water out

water washes over Siliphos

Siliphos spheres


The ONLY limescale inhibitor with a REAL money-back guarantee!


You’ll read much about so-called ‘limescale inhibitors’, how they will remarkably halt limescale - even though there’s actually nothing to them! Or maybe they use a magnet, or electronic waves. But only ONE comes with a ‘forever’ money-back guarantee...and that’s ours. And that really says it all. If you’re thinking of choosing something else, just ask them if you can have your money back in 15 years’ time.

The LimeStop is constructed from stainless steel, not plastic. It is replaced in 2 years (and thus works out from 16p a day). But when its work is over, the LimeStop is 100% recyclable.


It fits ‘inline’ with your piping, so is an easy-fit. We recommend that you install simple valves to make replacement easier. Can be fitted horizontally or vertically. Compression connections are provided.


Not only is the LimeStop adequate to protect all the appliances in your home...


The treated water is even safe for babies...unlike artificially-softened water!

It conforms to EN1208:2005 and WHO standards for drinking water supplies.



15mm - £125Credit and Debit Card Acceptance for small business with paya_card_processing_services

22mm - £125Credit and Debit Card Acceptance for small business with paya_card_processing_services

Delivery to UK mainland only

Ordering more than one? Please email us.

Replacements £115.00 including delivery


No electricity

No salt

No moving parts

No back-flushing

No smoke...no mirrors!


Compact size - just 280mm x 70mm (11” x 3”)



We’re well aware of products purporting to be water conditioners “aqua-conditioners” and even talking of ‘softened water’. They (often!) add zinc to the water, they sometimes use children’s magnets, they might even use an electronic wave. And yet not a single manufacturer of these devices will give you your money back in years to come if it doesn’t work. Now, doesn’t that tell you EVERYTHING about their product? It should. We know of one product where they won’t even tell you the price of it on their website (because it’s ridiculously expensive, yet it’s the same as a product for 1/10th the cost!). We know of another that says it has been tested by the German DVGW W512. What they don’t tell you is that this has been discredited because trial-testing is carried out under a SINGLE test pattern of one particular flow rate! That isn’t science. You should should look for one thing...your money back if it doesn’t work. We’ve been manufacturing limescale inhibitors since 2003...and we’ve never had to give anyone their money back.




LimeStop (stainless steel version) FAQs...


What’s the cost?

£125.00 including delivery (to UK mainland only).

What’s the installation cost?

We charge £80 for a typical installation (sorry, RG postcode area only). Many plumbers will charge you less than that, and you can fit it yourself.

What is the LimeStop?

The LimeStop is a limescale inhibitor – it inhibits limescale from forming. Some people call such devices ‘water conditioners’.

The majority of limescale inhibitors don’t work, do they?

No, they don’t. Many such devices use magnets, electrolytic action, or electronic waves. If they worked, then the manufacturers would offer you your money back on performance...but they don’t! Here’s the ‘guarantee’ on a popular-selling ‘limescale inhibitor’...

“We guarantee that your ********** will work for you. If you are not

satisfied with the performance after 3 months continuous use

please contact us within 30 days of the end of this period”


Really? Four months? It follows then that after just four months, when you find that this product (which costs more than £100) doesn’t actually work, then you won’t get your money back! Here’s another...

“If after six months of continuous use, you are dissatisfied with the

performance of your water descaler, you may return it for a full refund”


Again, after six months you’ll be unlucky when you discover it hasn’t worked! What good is this? If it really did work, then the manufacturer would surely be happy to give you your money back no matter when you made your claim?

So why is the LimeStop different?

The LimeStop uses Siliphos - silicate-polyphosphate, so it’s classed as a ‘physical’ limescale inhibitor, in that it actually uses something to inhibit limescale – there are no smoke and mirrors! Siliphos is remarkable stuff - able to positively halt limescale formation.

Is that why you guarantee it?

Yes, if you research ‘limescale inhibitors’ (on the internet, or even by phone) you’ll find that manufacturing companies of these devices will NOT give you your money back, years down the line, if they don’t work! WE WOULD. We can offer such an amazing guarantee because Siliphos really does work, even in very hard water.

Like where?

LimeStops have been installed in most parts of the UK, and have been sold in France, Spain and Belgium.

What are the dimensions of the LimeStop?

It’s compact at just 275mm x 70mm (approx 11 inches x 3 inches).

What does it weigh?

2 kg.

What’s inside that inhibits limescale?

Siliphos - a food grade material called silicate-polyphosphate.

How does it inhibit limescale?

As water flows through the LimeStop it flows over the spheres of Siliphos - and they give up a slight amount of their coating. Siliphos inhibits limescale in two ways. First of all it makes the calcium molecules stay in suspension, rather than stick. Secondly it lays down a layer of silicate-polyphosphate on the walls of pipes etc. This too helps to inhibit limescale sticking.

How much Siliphos is in there?

1,200 grams (500 grams more than our closest rival product!).

Why that particular amount?

Because around 1.2 kg is the optimum amount to ensure limescale inhibition in the average home for the first two years.

Does it remove limescale that is already present?

Yes, but it takes time.

Should it be fitted either horizontal or vertical?

Either, but refer to the installation instructions.

Does the Siliphos 'run out' of its effectiveness?

It degrades, that’s why replacement is required in two years. We will send you a reminder.

So what will be the continual cost of the LimeStop?

Just 16p a day! The cost of replacement (every two years) is just £115.00 including postage.

Is it a straightforward swap?

Yes, very.

Should I use a plumber to do that?

You could, but it really is very easy - you just need a spanner suitable for the connections. It really is a 5-minute job!

Is the water drinkable?

Yes, Siliphos is a non-hazardous, food-grade material. It conforms to EN1208:2005 and WHO standards for drinking water supplies. Unlike artificially-softened water, it's safe for babies too.

Do you supply a ‘check valve’ anyway?

Yes, we do. It’s in the box.

Is it classed as a water softener?

No, the hardness is still there, it's just suspended. This is true of all limescale inhibitors; if a water conditioner doesn't actually remove the calcium, then it's not a water softener.

If the treated water is then stored, will it still be effective?

Yes, but the sooner the stored water is used, the better.

I don’t have a 15mm mains water connection

No problem, a 22mm version is available for the same price - just choose it above.

What do I need to install it?

You’ll just need some simple fittings, copper tube, a tube cutter, and basic tools - we’ll help you all the way.

Your instructions say not to fit the LimeStop too close to a heat source, why?

Warm water backfeeding down the supply will degrade the Siliphos. Its period of effectiveness would be less.

Is it easy to fit?

Yes, very. Fitting should take no more than 30 minutes.

What if there is hardly any pipework to fit it on?

That’s no problem. All you need to do is re-locate the LimeStop away from the piping. You can route the piping both to and away from the LimeStop with flexible hoses, so you really need just over 3” of piping.

Can I fit it in a cupboard?

Yes, but not if the ambient temperature is above 30 degrees C for the same reasons as above. Also, fit it low down in the cupboard where the cold mains enters, as it would be the coolest part of the cupboard.

Will I still get limescale around my showerhead?

Most possibly, yes. This is because although that the Siliphos-effect will stop your shower scaling-up, 'still' water (water that doesn’t move) will be left on the showerhead and around taps etc. The effect will be lost and deposits may well occur. But these can simply be wiped away, as the deposits aren’t sticky.

What will the LimeStop protect?

*The LimeStop is made for ‘mains’ water appliances, such as mains-pressure thermal store hot water heaters, dishwashers, washing machines, showers, etc.

What about ‘Megaflow’ type units?

These use a store of hot water, but they are technically ‘heat banks’ and not thermal stores. We can only state that the sooner the water is used after running through the LimeStop, the better. The LimeStop TS is perfect to protect thermal store hot water cylinders, that’s why it’s called ‘TS’!

What size ports has the LimeStop got?

The LimeStop is supplied with either 15mm or 22mm fittings - you choose.

Will my water pressure be reduced?

The LimeStop is a through-flow unit, and you would not see any noticeable drop in water pressure or flow after fitting.

Will the LimeStop withstand high water pressures?

Yes, it is a very robust unit made of stainless steel.

What is limescale?

It's dissolved rock. Rain water dissolves the calcium and magnesium out of the rock. This water is then treated and sent to your home. When the water is heated the dissolved particles re-solidify and stick to the walls of the heat exchanger. It will do this at low temperatures, but really begins at anything above 63 degrees C.

Is limescale harmful?

To your heating appliances, yes, very!  Even a tiny coating of it will reduce the efficiency of your appliance, meaning your energy bills will be higher. It also causes premature failure of key components. However, to your body, it is beneficial. Remember, water softeners remove this beneficial calcium, the LimeStop doesn’t.

Why is the LimeStop better than other limescale inhibitors?

The LimeStop requires no electricity or maintenance. It doesn't use questionable electromagnetic waves. It uses a time-proven material that we feel good enough to offer our performance guarantee of your money back. And you don’t have to fiddle with large 'O' rings and wet Siliphos - you simply replace it. You may be aware of a very similar unit to ours, but it requires 6-monthly topping up, with annual cleaning and Siliphos replacement.

Do you guarantee that the LimeStop works?

Yes, we do. Our guarantee is that stated formally below. We believe all limescale inhibitors should carry a performance guarantee.  Don't buy one that hasn't got a money-back guarantee.

Have you ever had to give anyone their money back due to re-scaling?

No, never.

How can I get one?

Just click on a ‘BUY’ button above. Any questions, simply email us.

Do you give a discount if I buy more than one?

Yes, of course, just email us.

I have soft water, so surely I don’t need a LimeStop?

The LimeStop can even be used in soft water areas, as the Siliphos lays down a protective coating on the walls of the supply piping - thus preventing acidic-water attack and so-called ‘Blue Water’.

Why don’t you sell the LimeStop in plumber’s merchants?

Because by the time they have added their mark-up charge, it would make it too expensive. You get it at the cheapest possible price by buying direct from us. It should arrive within two working days by courier.


Why we are not on Amazon.

We don’t support Amazon, and its woke politics of cancel culture. We will not buy any products from Amazon and will not have anything to do with the company.


Why we will NOT offer PayPal.

PayPal is a very ineffective and poor payment facilitator. It does NOT protect you in many circumstances, and its ‘Resolution Service’ even circumvents British consumer law! It isn’t good for us, because PayPal’s charges would make our products more expensive, and it isn’t good for you because it takes too long to settle any disputes. We advise that you are much safer using your credit card, as that protects you under Section 75 of the Consumer Credit Act. What is actually needed is a government-controlled escrow scheme. Don’t hold your breath waiting for that!



Please be aware that items are usually sent by courier, which is a 2-day service, but this cannot be guaranteed.



The guarantee against ‘scaling-up’ is dependent on the LimeStop being installed for 30 months and at least one replacement. If the protected appliance/s* should ‘scale-up’ to the detriment of water flow (we would require proof to satisfy such an occurrence), then we would return the original purchase price to the original purchaser minus the delivery charge. Your statutory rights are not affected.

*Protected appliance/s: The unit purchased must be stated as suitable for its application.








19 Cockney Hill, Reading. RG30 4HF





Made in Berkshire, England





Last update Feb 1, 2021




Truly remarkable limescale inhibitors

Stop limescale...or your money back...GUARANTEED

...from 1/6th the price of a water softener!



PLEASE NOTE: Payment is taken by ‘Payatrader’ not us. If you have any problems with payment (technology often fails!) please email us HERE to let us know.

Thank you.



The stainless steel version in our brilliant LimeStop range

Protects your home against limescale...

Boiler, Hot water cylinder, Dishwasher, Washing Machine, Shower...*


and all from just 16p a day - contains 1.2 kg of Siliphos!