woman enjoying swim spa

How to Test for Hard Water?

The majority of people who have installed either a traditional swimming pool or swim spa in their outdoor living space have one thing in common. One thing they often complain about is the hard water being used in their pool installations. 

Hard water, according to pool and spa warehouse managers, is characterized by having a relatively high concentration of calcium and magnesium, alongside other natural metals and minerals. 

Even though hard water is not known to cause any kind of serious health concern, it can become a major problem because they often lead to excessive buildup of scale in boilers, water pipes, hot water heating systems, and a sundry of other equipment that makes use of water to function/operate. 

woman soaked in hot tub

What can be considered as an even bigger nuisance of hard water is that they are not as effective when used for cleaning purposes as well as soft water. You won’t be very satisfied to use hard water when doing laundry or washing your dishes. It is quite annoying to use hard water on such a common household chore because it will require you to use more cleaning agents or soap to create more suds. 

It is such a relief to know that there are a couple of ways we can test or measure out hard water levels. So far, the most accurate and reliable though is carried out by an independent laboratory. 

You only have to provide them with sample water. Perhaps what can be seen as a setback here is that these independent laboratory testing can be a bit expensive to many and that it will take a significant amount of time to get results. 

If you are looking for a quick but somehow inexpensive way to measure hard water level (but there is a good possibility that it is less precise also) is by trying out one of the following methods. 

Soapsuds Test

People working in the various pool and spa warehouses recommend the use of a glass or plastic bottle that comes with a tight-fitting cap if you want to try the soapsuds test approach. With this method, you need to fill your bottle with 1/3 tap water taken directly from your faucet. This should come around 8-10 ounces. Allow the bottle to settle and wait for the results. 

Then drop a few dollops of any kind of dishwashing liquid. See to it that you are using pure liquid soap for this purpose and not some qualified ‘detergent’. Once done, shake well for 10 seconds and allow it to settle. Wait for the results. 

  • If your soapy solution foams up rather faster than expected — meaning to say there are a lot of suds and the water found below the suds would be relatively clean, take this as an indication that you have a fairly soft water quality. 
  • The issue comes when your soapy solution would not foam up well enough. Sometimes what you’d see is just a shadowing layer of suds. As for the water below it, it would be cloudy. If this is the case, you likely have hard water from your faucet.

DIY Test Kit

The majority of home improvement or hardware stores, as well as a handful of online retailers, are offering DIY home test kits for water quality. You can check them out if you want to try this alternative approach.

Most managers of a pool and spa warehouse suggest that you only consider using a test kit that is provided by a reputable water testing manufacturer, look for a particular product offering that can test out the hardness of the water. Know that there are test kits that can only handle specific contaminants such as radon. 

As for many others, they test out for overall water safety and quality.  

If you are familiar with the wet-strip test, this is the simplest and the easiest way you can test out your pool spa water. What you’ll do with this technique is to fill out a container using tap water and immerse your test strip in it.  

You will compare the resulting test strip to the kit’s standard chart. Based on this result, you can gauge how hard your tap water is with respect to the test kit user manual or instructions.  

Wrapping up!

Normally, the hardness of water is reported in milligrams per liter or mg\L of calcium carbonate. Jot down the resulting calcium carbonate measurement you have and have this compared to the following scale which is the accepted standard of the US Geological Survey:

  • Soft water is around 0-60 mg/L
  • Moderately hard water would be anywhere between 61-120 mg/L
  • Hard water would be anything between 121-180 mg/L
  • Very hard water if your test kit readings are over 180 mg/L