The harder your water is, cleaning products become less effective as hard water causes difficulty in creating a soapy lather. Hard water also creates crusty deposits – known as scale – in your washing machine or dishwasher. Softer water lathers well when detergent is added.
You can think of water hardness as a tough stain that interacts with the ingredients in your washing detergent, and stops your detergent from working effectively. When washing with hard water, good detergents include extra ingredients that soften the water so the rest can get to work removing the real stains.
Tell-tale signs of hard water include a “ring around your bathtub,” soaps and shampoos do not lather easily, white residue forms around faucets and drains, and fabrics feel stiff, not fluffy. Detergents are less sensitive to the minerals in water; so they perform better and don't form a curd.
The effectiveness of powdered detergents decreases in hard water. This is due to anionic surfactants combining with the divalent calcium ions in the hard water to form a scum that is not water soluble. This reduces the efficiency of the detergent.
Hardness in laundry water is a problem because the minerals that cause hardness interfere with the cleaning action of soaps and detergents. As a result, larger amounts of soaps and detergents are needed to counteract the minerals, and laundry results are not as good as when there is no hardness present.
Water that has been softened by a water softener, typically replaces the magnesium and calcium minerals with sodium or potassium; these minerals do not react with the compounds in soap or detergents so they perform as they were intended.
Soft Water Has More Washing Power
When using hard water, you'd need to add more warm or hot water to get your laundry clean and make sure the detergent is gone. Soft water will let you clean your clothes using the only ½ the amount of the detergent, and you can use cold, warm, or hot water to get it super clean.
Detergents are better cleansing agents than soaps because they can be used even with hard water. The charged ends of detergents do not form insoluble precipitates with calcium and magnesium ions in hard water but soap doesn't work in hard water. They do not form scum in hard water.
Detergents work better in hard water than soaps. Detergents lather in hard water when soaps do not. Below is a drawing of a molecule of detergent made from palm oil, called sodium lauryl sulfate. The two ends of the molecule are non-polar & polar.
The harsh nature of hard water can also lead to the premature fading of dark fabrics. This can look like red-brown spots and streaks on clothing from elevated iron levels. In the most extreme cases of hardness, the minerals can weaken clothing fibers and lead to tearing and holes.
Detergents react with minerals, but with water soluble results. So detergents work in both hard and soft water, although some of the detergent will get taken out of action, the more minerals present. So, you don't need as much detergent if the water is softer.
Soaps are not suitable to be used for washing clothes with hard water. Calcium and magnesium ions present in hard water combine with the soap, forming insoluble sticky grey precipitate called scum. This results in the wastage of soap.
Hard water, which has higher concentrations of dissolved minerals than softer water, reacts with the natural fats and acids of soap and creates soap scum. Soapless detergents do not have the properties that cause soap to do this, so they are perfect for hard water situations.
Best for Tough Stains and Hard Water
In fact, in our ratings, 12 Tide detergents (liquids and pods/packs) offer near top-level efficiency in hard water. Hard water contains high levels of calcium and magnesium that can leave residue on your clothes and mineral deposits inside your washing machine.
You may have to wash your belongings multiple times in hard water just to get them to feel and look clean. On the other hand, soft water doesn't contain minerals that prevent soap from making suds. So you can use less soap for the same job and get better, cleaner results.
Detergents cannot be used to check the hardness of the water, as they lather easily in both soft and hard water. However, the hardness of water can be detected using soaps, as soaps don't lather easily in hard water.
Some detergent boosters are formulated to condition hard water and optimize a detergent's cleaning ability. Natural products like distilled white vinegar and baking soda can improve the cleaning results of detergent. Boosters should be used along with the regular amount of detergent recommended for each wash load.
Three boosters to try are white vinegar, borax and washing soda. You should use them individually and not in combination with each other to avoid chemical reactions. These boosters work by changing the pH levels of water, thereby increasing the effectiveness of any laundry soap.
Hint: Detergents are not like soaps. They work well even with hard water and are more effective than soaps.
Hard water will also cause problems for your skin and hair. The deposits left on the skin will dry the skin out and cause itchiness and other irritation. Children with eczema are especially sensitive to hard water. Hard water can also clog pores and coat the air, making it more prone to dullness.
The Effects of High and Low Hardness
Specifically, water with high calcium hardness gets cloudy unless the alkalinity and/or pH are low enough to compensate. As mentioned, the excess calcium carbonate will precipitate as crusty, grayish white scale on surfaces, piping, and equipment.
Hard water interferes with almost every cleaning task, from laundering and dishwashing to bathing and personal grooming. The amount of hardness minerals in water affects the amount of soap and detergent necessary for cleaning. Soap used in hard water combines with the minerals to form sticky soap curd.
The ingredients in liquid detergents tend to react less with minerals in hard water, allowing them to work more effectively. This doesn't mean powder detergents are a no-go, though: Some water-softening ingredients, such as sodium carbonate, often come in powder form.