How Hard is Too Hard? A Water Hardness Guide

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Limescale on TapsMany areas in the UK and Ireland suffers with very hard water. This hardness is caused by a high mineral content in the water, in particular calcium and magnesium carbonates. Due to the UK and parts of Ireland being situated on porous rock formations, minerals from such deposits as chalk and limestone end up in the water supply.

Water Hardness does not have any adverse effects on your health so that, at least, is not a concern. However, there are other problems caused by Hard Water, the most commonly known issue being that of limescale.

So just how hard is too hard when it comes to water?

Water Hardness Level

Here’s a helpful table demonstrating the differences in water hardness. We’ll get into the nuances of this later, but this is a good place to start.

CaCO3 mg/lHardness Level
300+Very Hard
201 - 300Hard
151 - 200Moderately Hard
101 - 150Slightly Hard
51 - 100Moderately Soft
0 - 50Soft

As the above shows, anything over 100mg/l is considered hard water. Ideally, you need a level between 0 – 50mg/l in your water supply. However, context is important. Is it necessary to get your water hardness all the way down to the lowest possible bracket? Well, that depends…


How Hard is Too Hard?

In an ideal universe, you’d always want your water down to 0 – 50mg/l. At this level, limescale build up is practically non-existent and all the other issues with hard water (see below) are largely rectified. As with all things, context is important though, and dependant on the application the amount of “wiggle room” you have can differ.

If we consider a standard residency with a water hardness level of about 60 – 70mg/l, then there’s unlikely to be any pressing issues. Limescale may still be a factor, however it’s going to take a much longer time to start to form and build up, compared to a residency with a hardness rating of 200mg/l+. Of course there is the unseen damage to pipework, heating and so on, however it may take quite a long time to manifest.

A brewery, restaurant or other similar business will definitely want to drag that water hardness level right down to the 0 – 50mg/l level. Not only is their water demand much higher than a household, and therefore more water passing through means more exposure to the water hardness, but maintaining appliances such as dishwashers, coffee machines or machinery and equipment used in creating products needs to be kept as clean and efficient as possible.

Limescale build up on these machines can mean more frequent maintenance is required and costly repairs. A top level water quality for producing products such as beverages or even meals is also paramount and water hardness may affect the final product’s taste or quality.

Finally, you have large industrial use, such as a pharmaceutical manufacturer, nuclear power applications and water cooling requirements. There’s no room for error in these applications and often, the water needs to be as pure as it can get. Water hardness in these instances would absolutely have to be 0 – 50mg/l… and preferably as close to zero as it can possibly get.

The Problems with Hard Water

As already mentioned, Hard Water is not a concern for your health and the main issue it causes is limescale. However, to go into more detail, there are many issues and problems that hard water can cause:

> Limescale build up on appliances such as kettles and forming on showerheads and taps. Toilets can also start to form limescale. Heating and water pipes can also start to become clogged, reducing water flow and pressure.

> The same is true for other appliance such as washing machines or dishwashers. These can be subject to the same limescale build up, reducing their reliability and increasing the likelihood of a breakdown.

> Shampoo and soap does not lather as easily, requiring you to need to use more of the product.

> Clouding on any glass that contacts the water, such as shower screens and drinking glasses.

> Skin conditions can become irritated such as Eczema and hair and skin can become dull.

> Washing clothes and towels can become stiff and rough, whilst pale and white clothing can end up turning grey. Coloured fabrics can also lose their brightness.

> Weak water pressure can result in boiler rumbling. The build up of limescale here also reduces the efficiency and lifespan of the boiler, resulting in more frequent break downs and costly repairs. Energy bills will also increase as the boiler needs to work harder to heat the water.

Water Softeners

Duplex Water SoftenersWater Softeners come in many shapes and sizes, from the elegant and petite cabinet softener for a small house, all the way up to huge duplex water softener systems for industrial applications. Water Softeners remove the hardness from the water via an ion exchange process. This removes the calcium and magnesium ions from the water and replaces it with sodium ions.

A common concern with Water Softeners is that they increase the sodium content in the water, making it more “salty.” Firstly, you will not be able to taste this in the water and the sodium levels are usually still below the threshold for the water to remain drinkable. However, if sodium content does become too high or it is a major concern, further water treatment such as a Reverse Osmosis system can help to remove the sodium from the water.

Bespoke Water Treatment

J&F Water Treatment can provide water softeners to suit all requirements, from small residency requirements to commercial and industrial needs. We offer a full range of water treatment solutions and we’re highly experienced in putting together bespoke systems specifically for each individual’s requirements. If you have an enquiry, then please feel free to get in touch via email or give us a call.

UK Office Enquiries – or call us on 01538 399048

Ireland Office Enquiries – or call us on 067 34222

bird made up of water

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