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The AquaTru Under Sink Alkaline is an under sink reverse osmosis filter with an alkaline mineral stage. It fits in the cupboard below the kitchen sink and feeds its own tap on the worktop. Water goes through four stages before it reaches your glass.
A pre/carbon filter takes out sediment and chlorine. The reverse osmosis filter removes lead, arsenic, fluoride and other dissolved metals. The last stage is a pH+ VOC carbon filter that adds minerals back. It is certified by IAPMO to NSF/ANSI standards to reduce 84 contaminants, including PFAS and microplastics.
The storage tank holds up to 1.7 US gallons, about 6.4 litres, ready to pour. A leak detector sounds an alert and shuts off the cold water line by itself. The control panel shows filter change alerts and battery status.
It is reverse osmosis with a mineral stage at the end. The RO membrane removes contaminants and most minerals. An alkaline filter then adds minerals back and lifts the pH. In this system that job falls to the pH+ VOC carbon filter, which is stage four of the four.
The RO storage tank holds up to 1.7 US gallons. That is about 6.4 litres of filtered water ready to pour. It refills by itself from the cold water supply. A family can draw water through the day without waiting for a batch to filter.
It connects to the cold water line under the sink and needs a hole for its own tap. The box has the tubing and an installation kit. Many people fit it themselves. If you are not sure about drilling a worktop or sink, a plumber can do it quickly.
It is certified by IAPMO to NSF/ANSI standards to reduce 84 contaminants. These include lead, chlorine, chloramine, fluoride, arsenic and chromium 6. It also covers microplastics and PFAS forever chemicals. The pre/carbon stage deals with sediment and taste first.
The pre/carbon filter lasts up to 6 months. The VOC carbon filter lasts up to 1 year. The reverse osmosis filter lasts up to 2 years. Real life depends on how much water you use and how hard it is. The panel warns you when a change is due.
The leak detector sounds an alert straight away. It then shuts off the cold water line to the unit by itself. That stops a small drip turning into a flooded cupboard. You can then check the fittings and press reset on the control panel.
It suits busy kitchens that use a lot of water. You get a tap on the sink and a tank that refills itself. The countertop models need no fitting but you fill them by hand. Both use the same four-stage reverse osmosis idea.
You get the under sink manifold, the pre/carbon filter, the RO filter and the pH+ VOC filter. There is also the RO storage tank, a polished chrome faucet, tubing and the installation kit. A TruPure RO sanitiser for cleaning the tank is included. It has a 1-year warranty.
| Brand | AquaTru |
| Model | Under Sink Alkaline |
| Type | Under sink reverse osmosis water filter |
| Installation | Under sink, dedicated faucet |
| Filtration stages | 4 |
| Stage 1-2 | Pre/carbon filter |
| Stage 3 | Reverse osmosis filter |
| Stage 4 | pH+ VOC carbon filter (alkaline mineral boost) |
| Contaminants reduced | 84 |
| Certification | IAPMO to NSF/ANSI standards |
| Removes | Lead, chlorine, chloramine, fluoride, arsenic, chromium 6, PFAS, microplastics |
| Storage tank | Up to 1.7 US gallons (about 6.4 litres) |
| Pre/carbon filter life | Up to 6 months |
| VOC carbon filter life | Up to 1 year |
| RO filter life | Up to 2 years |
| Leak protection | Leak detector, alarm and automatic cold water shut-off |
| Control panel | Filter change alerts, battery status, leak detection, reset button |
| Faucet finish | Polished chrome |
| Included | Manifold, 3 filters, RO storage tank, faucet, tubing, installation kit, TruPure RO sanitiser |
| Warranty | 1 year |