By The Zagosa Team. Published .
Reviewed or updated .
Balancing pH and alkalinity in your hot tub
Keeping your hot tub water clean is the goal, and depending on how you go about it, that can feel like hard work. The good news is you can improve the water quality by keeping pH and alkalinity in check. These two make or break whether the water is safe to use, so if you want a stress-free soak with no worries about harsh chemistry, these tips will help.
It is easier said than done. Balancing pH and alkalinity in your home hot tub can look like more effort than it is worth at first glance, all that pouring products into the water. But once everything is balanced correctly, day-to-day maintenance gets a whole lot simpler.
The water management team at Zagosa Spa & Pool has pulled together this guide so you can stay on top of your hot tub water chemistry. We will look at what causes high pH and alkalinity and what to do when your readings come back high on either.
What is the difference between pH and alkalinity?
Alkalinity, or total alkalinity (TA), measures how well your water can neutralise acids, which makes it central to balancing your pH. It acts as a buffer, helping the water resist sudden swings. If it is out of balance, your pH readings can drift too high or too low. Your hot tub alkalinity should sit between 80 and 120ppm.
pH, on the other hand, measures how acidic or alkaline the water is. The ideal range for a hot tub is 7.2 to 7.8, because that is where chlorine works best at keeping the water clean. Check your pH at least twice a week, since sanitisers and minerals in the water can move the reading.
The problems with high pH and alkalinity
Unbalanced alkaline levels can harm your tub's appearance, throw off your pH readings and even affect your skin.
High pH readings can cause scale to build up on your components. Deposits on the surface of the spa can leave the water cloudy, dull or even foamy, and they knock the efficiency of your sanitiser, which in turn raises the risk for friends and family using the tub.
How to address high pH and alkalinity
Balancing pH and alkalinity follows the same principle. If your levels are low, use a pH increaser and a total alkalinity increaser. Always follow the rule of thumb and balance total alkalinity first, then pH. If your levels are too high, reach for a pH and alkalinity reducer, or minus product.
If your alkalinity is too high, we would suggest a combined pH and alkalinity reducer, because usually if your water is high in pH, or naturally high pH from the source, your alkalinity tends to follow.
If your pH is too high, again we would suggest a combined pH and alkalinity reducer, since if your water is high in alkalinity, or naturally high TA from the source, your pH usually follows suit.
To get the chemistry right, remember the rule of thumb and always balance your alkalinity before you touch your pH.
The balancing act of pH and alkalinity
We have spent years in the water treatment industry, and you are not always going to get the balance right first time. But as a rule, if you set the correct levels to begin with, they are easier to keep there.
Bear in mind your readings can shift for all sorts of reasons. If the water in your hot tub is over three months old, it may have reached chemical saturation. When that happens, even adding the right products in the right order tends to have little effect, and it is time for a water change.
It is also worth saying that water treatment chemicals are like a lot of things: you get what you pay for. There are plenty of poor-quality, heavily diluted batches out there, which just means using far more product than you would with a better supplier.
For peace of mind, every chemical we supply at Zagosa Spa & Pool is top quality and stored to industry standards in our own warehouse. That is simply how we like to work.
Our water management team is always happy to help with your hot tub chemistry. Get in touch today on 0333 339 4043.