How do I Test my Spa Water’s pH Level?

Having a good understanding of how to look after your spa pool water is crucial to maintain the product’s lifespan. A large part of that is making sure your water’s pH level is where it needs to be.

As you may remember from high school chemistry, pH is the measure of how acidic or basic a substance is. If your water’s pH is out of line in either direction it will cause skin irritation, and has the potential to corrode your spa pool’s componentry. To begin this process, you’ll need to have your Test Strips on hand.

To start, you will simply pick a test strip out of your bottle, and dip it into the centre of the spa water, before holding it there for approximately ten seconds. Following that, you will pull the test strip out of the water, flick off any residual droplets and wait 30 seconds to see your results. You will now be able to compare these results to the key provided on the back of the test strip bottle, just like our example above. You want to see a test strip colour reading that’s somewhere between 7.2 and 7.8 – right in the middle of the pH scale. If your pH is out of line, you need to look at your total alkalinity reading, as these two usually work together, when one is out, often the other is too.

Check Total Alkalinity First

Total Alkalinity (TA)  acts as a bodyguard for your pH. It directly helps to stabilize pH by taking the brunt of any changes to the water from acidic or basic substances. This is why it’s best to always get your TA set in the correct range first, then move on to adjusting your pH, especially when starting up the spa.

Check the TA reading using the test strips:

If TA is too low, simply increase using pH Buffer (iluka elevate)to get it set within the correct range (80 – 120ppm). Then move on to pH.

If TA is too high, you can reduce it by using pH Decrease (iluka descend), but keep in mind that this will also decrease pH. If your pH gets pushed too low, you might need to purchase some pH increase. We’ll discuss raising pH in the following section.

How to fix a low pH reading

Low pH is somewhat of a rare occurrence in metro areas with a town water supply, which is why pH increase is not included in the startup kit by default. However, If your pH is frequently low, you will want to purchase some pH Increase to bring it back up. You can also raise pH naturally by aerating the water. This can be done by opening up the air venturis within the spa and running the pumps for a few hours. Keep in mind this is only useful for small raises in pH.

How to fix a high pH reading

On the other hand, if your pH reading is above 7.8, you will need pH Decrease to bring it back in line. We provide handy tables in our Spa Pool and Watercare Handbook which you can refer to for dosing. Use this guide to measure your required dose.

We recommend mixing chemicals in a bucket full of water to ensure they are completely dissolved, before turning on your jets and adding the mix to your spa water to allow circulation.

All necessary chemicals and products are available through Spa Supplies where you can subscribe to any products you require on a recurring timeframe of your choice. This subscription will save you 30% on the total cost while ensuring you never run out!

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