A guide to hard water, limescale, and the straightforward steps that keep your AquaTru performing as it should.
When an AquaTru begins filtering more slowly than it once did, there are generally two explanations. The first is that the unit is due for routine maintenance, perhaps a filter change or a descale. The second, common in hard water regions, is the mineral content of the water itself, which gradually deposits limescale inside the system.
Neither situation is unusual across Europe, and in most cases slow filtration can be put right with ordinary care. It should not be taken as an automatic sign of a manufacturing fault. This blog explains what is likely happening and what you can do about it.
What Is Hard Water?
Hard water simply means water carrying a high concentration of dissolved minerals, principally calcium and magnesium. Rain falls soft. As it filters down through soil and rock, it passes over formations such as limestone and chalk, which are rich in these minerals, and dissolves a little of them along the way. The longer the water spends in contact with such rock, the harder it becomes before it reaches your tap.
This is why hardness differs so much from one place to another. A European survey of groundwater chemistry, drawing on more than 7,500 measurements across the continent, found that calcium levels vary considerably depending on the underlying bedrock. Regions built on limestone and other carbonate rock tend towards hard water. Those on granite and similar hard, less soluble rock tend towards soft. Two households in neighbouring countries may therefore have very different water.
Hard water is safe to drink. The EU Drinking Water Directive sets no limit for hardness, calcium, or magnesium. Both are essential minerals, and as McGill University's Office for Science and Society explains, the quantities found in hard water can make a modest contribution to your daily intake. The difficulties hard water creates are practical rather than medical, and they begin with limescale.
Knowing the hardness of your local supply is worthwhile, as it allows you to plan maintenance sensibly.
How Hard Water Affects Your AquaTru
Wherever hard water flows, it leaves a little of its mineral content behind. You will recognise the result as the white, chalky coating that forms inside a kettle. That coating is limescale, and it appears inside water systems for precisely the same reason. As water passes through or sits within the unit, small quantities of calcium and magnesium settle onto the internal surfaces and accumulate steadily.
Within a reverse osmosis system such as AquaTru, these deposits gradually coat the components the water travels through, the membrane among them. The more they build, the narrower the path available to the water, and filtration slows accordingly. The unit has not failed. Its internal channels have simply narrowed, much as limescale narrows a kettle or a pipe. This effect on reverse osmosis membranes is well documented.
Encouragingly, the process can be prevented, and if addressed early enough, it can be reversed. Remove the limescale through descaling and the water flows freely once more, with normal performance restored.
Keeping Your AquaTru at Its Best
Caring for your AquaTru asks very little. Your user manual sets out the essentials, and the steps below will keep the unit working as it should for longer.
Know your water hardness. AquaTru performs best with water up to 171 mg/L, roughly 9.5 °dH. Harder water does not prevent you from using the unit, but knowing where you stand allows you to plan your maintenance accordingly.
Descale regularly. Descaling is the single most effective way to prevent limescale from building and to preserve filtration speed. The AquaTru Descaling Kit (Classic and Carafe) uses natural, food-grade citric acid, which dissolves the calcium and magnesium deposits gathering inside the system. The acid reacts with the limescale and breaks it down so that it can be rinsed away, clearing the internal channels and restoring normal flow without harming the components. Where hardness is moderate, descaling twice a year is sensible. In hard water regions, monthly descaling is advisable. Short visual walkthroughs are available for the Classic and the Carafe.
Consider a water softener in very hard regions. Where hardness is pronounced, a softener fitted to your supply will reduce the mineral load before it ever reaches your AquaTru. Softeners work by ion exchange. Hard water passes through a bed of small resin beads carrying sodium. The calcium and magnesium are drawn out of the water and held by the beads, which release a little sodium in their place. What emerges is softer water that forms far less limescale.
Replace the RO filter as needed. In hard water regions the reverse osmosis filter works harder, and may need replacing rather more often than it would elsewhere. This is entirely normal, and simply part of keeping the unit producing clean, great tasting water. Filter bundles are more economical than buying individually, and occasional sales offer a further chance to reduce the cost of replacements.
It Is Not the Hardness That Matters Most
If the minerals in hard water are harmless, why filter at all?
Because calcium and magnesium are not the only things dissolved in tap water. It may also carry chlorine, lead, microplastics, pesticides, pharmaceutical residues, and other chemicals. Those are the contaminants worth removing, and removing them is precisely what AquaTru is built to do. Its four-stage reverse osmosis system removes up to 99% of impurities and reduces total dissolved solids by up to 97%, with performance certified by IAPMO to NSF/ANSI standards.
Whatever the hardness of your water, AquaTru delivers the same clean, filtered result.
Get the Most From AquaTru
Hard water is part of daily life for a great many households across Europe, and slower filtration is its most familiar consequence. It is seldom a fault, and it is readily managed through regular descaling, an awareness of your local hardness, and the occasional filter change.
More to the point, hard water is no reason to go without properly filtered water.
Already own an AquaTru? A little routine care is all it asks. Not yet? There has never been a better moment to make the change.
Browse the AquaTru range and choose pure, great tasting water for your home. If you have questions about your unit or which model suits you best, our team is always glad to help.
