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AquaTru makes reverse osmosis water purifiers for the home. Every model runs the same patented 4-stage process, which the brand calls Ultra Reverse Osmosis. Tap water is pushed through a pre/carbon filter, a reverse osmosis filter and a VOC carbon filter. What comes out is close to pure water, with a clean taste and very little left in it.
Most jug filters only use carbon. Carbon improves taste and takes out chlorine, but it does little for dissolved metals, nitrate or fluoride. A reverse osmosis water filter does, which is the main reason people pay more for an AquaTru than for a basic pitcher. The AquaTru Classic and AquaTru Carafe are compact countertop water filters with no installation. The AquaTru Under Sink is a plumbed water filtration system. Every unit is independently tested and certified to NSF/ANSI standards by IAPMO.
On the alkaline versions, stage 4 is a pH+ VOC filter. It does the same job and then adds minerals back and raises the pH. The rest of the filter system is identical. The result of this purification is clean water with a neutral, great-tasting finish, whichever model you buy.
The AquaTru Classic is the original countertop model. You fill a 4 litre tap water tank at the back. About 12-15 minutes later the front tank holds 2.7 litres of filtered water, poured with a button. It needs a plug socket but no plumber. The body is BPA-free Tritan plastic and the unit weighs 7.3 kg. It suits a couple or a small family who drink a few litres a day.
The AquaTru Carafe is the smaller, newer countertop unit. It has a 2.5 litre tap water tank and fills a 1.9 litre borosilicate glass jug in roughly 10-15 minutes. You lift the jug out and take it to the table or the fridge. At 4.08 kg it is the lightest of the three. People who dislike plastic, or who have little worktop space, tend to pick the AquaTru Carafe.
The AquaTru Under Sink connects to the cold supply in the cupboard and feeds a separate tap on the sink. Filtered water flows straight away from a storage tank, which refills over 2-3 hours. It is listed for 84 contaminants and adds a leak detector. A plumber or a confident DIYer is needed to fit it. It suits families and kitchens that use a lot of water for drinking and cooking.
If you like the idea of a plumbed system but want more brands to compare, look at our tankless reverse osmosis systems, which skip the storage tank and filter on demand.
Figures come from AquaTru's own specifications and our product feed.
| Classic | Carafe | Under Sink | |
|---|---|---|---|
| Where it goes | Worktop | Worktop | Under the sink, own tap |
| Installation | Plug and play | Plug and play | Plumbed in |
| Tap water tank | 4 litres | 2.5 litres | Mains feed |
| Filtered water | 2.7 litre tank | 1.9 litre glass jug | About 6.4-7 litre tank |
| Time to fill | 12-15 minutes | 10-15 minutes | Ready on tap, refills in 2-3 hours |
| Contaminants (certified) | 83 | 4-stage, same process | 84 |
| Efficiency (AquaTru figure) | 75% | 63% | 25% |
| Weight | 7.3 kg | 4.08 kg | 7.3 kg |
| Alkaline version | Yes | Yes | Yes |
The efficiency line matters more than it looks. A countertop unit sends the rejected water back to the tap water tank, which you tip away before the next fill. The plumbed Under Sink sends it down the drain, like most under sink RO systems.
One or two people drinking water, tea and coffee are well served by a countertop model. A family of four also cooking pasta, rice and baby formula will refill a 2.7 litre tank many times a day. That is when the Under Sink earns its fitting cost.
The Classic needs about 36 cm of depth and height under the wall cupboards. The Carafe is smaller and lighter. AquaTru also sells a sliding tray for each countertop model, so the unit can sit under a cupboard and slide out to fill. Renters usually pick a countertop model because nothing is drilled. For other plug-in designs, browse our portable reverse osmosis systems.
RO removes minerals as well as contaminants, so the water can taste flat. The alkaline filter adds calcium and magnesium back and lifts the pH. Many owners say it tastes closer to spring water. It costs a little more per year, and you can switch between the two at your next stage 4 change.
AquaTru recommends water no harder than 171 mg/L, about 9.5 °dH. Much of south and east England, London included, is harder than that. The Drinking Water Inspectorate explains hardness and your water company can tell you your figure. In a hard water area, plan to descale the unit monthly with AquaTru's descaling kit. Otherwise limescale slows filtration and shortens filter life. Owners in very hard areas often find the pre/carbon filter needs changing sooner than six months.
Filter replacement is the main running cost. Each stage has its own lifespan, set by months or litres, whichever comes first. The control panel or light tells you when a change is due. Filters twist in and seal, so a change takes a few minutes.
| Filter | Classic | Carafe | Under Sink |
|---|---|---|---|
| Pre/carbon (stages 1-2) | 6 months or 2,270 litres | 6 months or 1,135 litres | 6 months |
| Reverse osmosis (stage 3) | 2 years or 4,540 litres | 2 years or 2,270 litres | 2 years |
| VOC carbon (stage 4) | 1 year or 2,270 litres | 1 year or 1,135 litres | 1 year |
AquaTru sells a 1 year filter pack and a 2 year filter pack for each model, in regular and alkaline:
A filter pack works out cheaper than single filters. For the Classic, the 1 year filter pack has two pre/carbon filters and one VOC carbon filter. The 2 year filter pack has four pre/carbon filters, two VOC carbon filters and one reverse osmosis filter. Check the pack says Classic, Carafe or Under Sink: Carafe filters do not fit the Classic. The AquaTru UK FAQ lists the exact capacity of each one.
The DWI advice on home water filters is clear on one point. Change cartridges as often as the maker says, or deposits and bacteria can build up inside. Regular maintenance also protects the warranty: AquaTru covers technical faults in the main unit for two years if filters are changed on time.
UK tap water already meets strict safety standards. An AquaTru is not about making unsafe water safe. It is about taste, peace of mind, easier hydration and less plastic waste. Chlorine taste, limescale in the kettle and worries about lead pipes, PFAS or microplastics are the usual reasons people buy one.
There is a fair counterpoint. The DWI notes that RO changes the natural make-up of tap water, and the World Health Organization recommends adding minerals back to RO water you drink. That is exactly the job of AquaTru's alkaline filter, so it is the version we would lean towards. AquaTru also sells a Perfect Minerals product for people who use the regular filter.
On cost, add up a year of filters and set it against what you spend on bottled water now. The more bottled water you buy, the faster an AquaTru pays its way.
AquaTru stands out for its certifications and glass jug, but it is not the only choice. Waterdrop and Frizzlife both make countertop and tankless units, often with hot water. Compare them in our Waterdrop reverse osmosis systems and Frizzlife reverse osmosis range. For a classic plumbed setup with a tank, see iSpring RO systems or APEC water systems. AquaTru's process counts as four stages; if you want more steps, such as remineralising and UV, look at 6-stage reverse osmosis systems.
The AquaTru Classic and the AquaTru Carafe do not. You plug them in and fill the tap water tank by hand. Only the Under Sink is plumbed into the cold supply, with its own faucet on the sink.
Yes. The RO stage removes fluoride, lead, arsenic and nitrate. The VOC carbon stage targets PFAS chemicals such as PFOA and PFOS. The systems are certified to NSF/ANSI standards 41, 53, 58, 401 and P473, tested by IAPMO.
The pre/carbon filter lasts about 6 months, the VOC carbon filter about 1 year and the reverse osmosis filter about 2 years. Heavy use or very hard water shortens that.
Not better, just different. The Carafe is lighter and pours into a glass jug. The Classic holds more filtered water, 2.7 litres against 1.9 litres, and its filters last longer in litres.
Every RO system rejects some water. On the countertop models it collects in the tap water tank and you tip it away before refilling. AquaTru quotes 75% efficiency for the Classic.
Yes. Because RO strips out the hardness minerals, filtered water leaves almost no limescale in a kettle or coffee machine.
