HARD WATER STAIN REMOVAL GUIDE

  • What is Hard Water? What causes it?


    Simply put, hard water is water that has high mineral content. It is formed when water filters through deposits of limestone and chalk. This type of water is full of minerals like calcium, magnesium, metal cations, and compounds such as sulfates and bicarbonates. When hard water comes in contact with glass, it can leave behind unsightly  "water spots" or "tear drop" shaped deposits. These white mineral stains which are basically calcium deposits or lime scale. These stains are also a common nuisance on shower doors/walls as well as homes with no water softener. When giving quotes, it is common to see hard water stains in basement/low windows where a garden tap is sprinkling onto them or where rain is splashing up from concrete or stone.


    Here at Window Cleaning Resource, we carry a wide selection of Stain Removers, that vary in degrees of effectiveness depending on how severe your stain is. So what's the best product for removing hard water stains? We get this question a lot and ultimately it depends on the stains. First, keep in mind that a Waterfed Pole alone will not do the trick, although a product such as the XERO Contact Scrubber can help but at the end of the day, you need to scrub/remove by hand. When it comes to hard water stains not all of them are created equal. You can start with a simple and mild solution and then progressively move towards a more heavy-duty solution.

  • Milder Solutions

    If you are dealing with mild hard water stains and want something gentle but effective, a paste or cream is the best way to go. These are not considered "harsh" products and generally have low fumes associated with them. The majority of these solutions can be applied with a towel, sponge or bronze wool.

    So what's the best way to tackle these stains? If you are using a paste or cream-based product just follow these general guidelines:

    • First, clean the surface entirely to remove any dirt/grime.• Next, apply the product. Press firmly and use a little elbow grease to buffer the stain out. This will loosen the stain. You can use a scrubbing pad or one of the products we discuss below.• Rinse with water until the glass is residue-free and then do your normal routine of cleaning and squeegeeing the window. You can repeat this process as needed.

  • Diamond Magic works well for mild to medium stains. If there are only a few windows, Diamond Magic works great but it is time-consuming. It's safe on you and the surrounding areas yet it's aggressive. It's a paste so just put some on a towel or sponge and buff the stains out. You can also apply it with a Sponge or even an abrasive.

  • Acidic Solutions

    If you are dealing with really bad hard water stains you may need something much more aggressive to get the stain(s) out. Before moving onto a more aggressive chemical ask yourself these questions: what is the nature of the stain? How long (approximately) has it been there? Is the stain on a coated piece of glass? Is the stain exposed to the sun for long periods of the day? Has the stain penetrated the glass? Either way, we are going to go over some of the most common acids used in hard water stain removal. It is important to note that when working with acids you MUST be very careful. At the end of the day, these are professional-grade acids that can cause injury if used incorrectly. It is also always useful to get your customer to sign a waiver.

  • Winsol Crystal Clear 550 Glass Restorer is a heavy-duty, aggressive cleaner.  A little goes a long way but as always, be sure to read the instructions for proper use. This product is designed to remove stage 1 alkaline particles, exhaust particles, chemical and mineral deposits, water spots, and runoff from brick, mortar, and concrete on glass. EaCo Chem OneRestore is also very popular. This cuts through hard water stains on glass and frames with little to no scrubbing.

Once you successfully combat hard water stains, consider getting your customer's windows sealed. Sealers will typically slow the build-up of hard water stains. Check out the Mr. Hard Water Protectant Sealant. If the window is clean and no mineral deposits are present, this is a nice it's way to protect the glass. It's is time-consuming to apply but it lasts a few months. It protects various surfaces from mineral deposit build-up. Safe to use on windows, shower doors, mirrors, metals, tile, fiberglass porcelain, and plastic.


  • Abrasives

    If you are using a milder hard water stain remover like some of the pastes mentioned above, it is a good idea to have scrubbing pads on hand as well. If you need something for more aggressive scrubbing, consider Steel Wool Grade 0000 or Bronze Wool. Many window cleaners prefer Bronze Wool over Steel Wool for the simple fact that it lasts longer and does not rust. Either option will work though. For milder stains, a scrubbing pad and a bit of elbow grease and buffering can go a long way! A damp Sea Sponge can come in handy and if buffering is needed, the Recycled Surgical Towels will come in handy as well.

    With these milder solutions, you often have to rub mechanically or manually. These are great to try before you move onto something more aggressive, such as products that chemically react to the mineral and change the chemical in the mineral to base. Do some research. If you understand a little about chemistry then you will understand what chemicals do to the minerals and what it does to the glass.

  • We carry a wide assortment of Window Cleaning Abrasives for whatever job is on the horizon. Pictured above for instance is the XERO Walnut Scrub Pad, great on surfaces where scratching is a concern.

  • The XERO White Scrub Pads have become very popular. Great to use when applying stain removers. This 6 inch x 9 inch pad doesn't scratch glass and these have a surprising amount of scrubbing power. A great abrasive to have on hand!

  • Another useful option is XERO Steel Wool. The XERO Steel Wool Pads are grade 0000 which are very important! Ideal for metal, marble, ceramic, and glass. Great as an aggressive scrubber as well as a detailer. Be very careful to check for rust before using these pads. A rusty steel wool pad is no good!


Don't know where to start?
Try one of our starter kits!

  • Ettore Stain Remover Kit


    Tackle hard water stains, calcium deposits, limescale, and soap scum with this helpful kit. The Ettore Scrub Off is a liquid paste stain remover for getting rid of hard water stains in bathrooms. Apply it with the included white scrub pads and use them to work the stains away. The towels make cleaning up easy.

  • Stain Removal Kits


    Customized by Alex at WCR, these kits will help easily remove all kinds of tough stains. Leave your surfaces cleaner and brighter with your option of these all-inclusive kits. Great for starting out or trying different solutions and products!

  • Aggressive Stain Removal Kit


    OneRestore from EaCo Chem removes pollution stains and white scum. This is a commercial-grade restorer and stain remover. This works for a wide range of stains including mineral and metal oxide. Use the included Unger Sprayer on a Belt and Walnut Scrub Pads to apply this chemical and get rid of stains.


Need hard water stain removal advice?
Ask an expert!

We know hard water stains so just get in touch with us! Let's chat! Be sure to check out all of our Soaps and Chemicals!


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