In today's post you're going to learn all about why you NEED a pool thermometer ...
And how choosing the right one can help regulate the quality of your pool water.
You'll also learn some important things to look for when shopping, and my recommendations for the best pool thermometers out there today.
Let's dive in, shall we?
Why you need a pool thermometer
Water temperature may not seem all that important, but there are definitely some valid reasons why it should be.
Depending on who is using your swimming pool and why, there could be even more reason to regulate the temperature than you think.
Swimming in water that's too cold
Getting into water that’s less than 60°F can feel like taking a dip in the arctic in a swimsuit.
While 60 degrees Fahrenheit doesn’t sound all that cold, remaining in water temperatures this low can often lead to cold shock.
According to Livestrong, water this cold widens the blood vessels so that warm blood will flow more freely to increase body temp.
But then your body will start shrinking them after a while to save your organs.
Since your body can’t maintain this state of restricted blood flow for long, when they do open back up, cold blood starts flowing through, which is the condition that can lead to hypothermia.
Yikes!
Swimming in water that's too warm
You might be thinking it’s difficult for water to be too warm since hot tubs are perfectly fine, but the truth is that hot tubs were never meant for prolonged use.
Also, you are usually not as active in a hot tub, so there is less risk of dehydration.
When you’re swimming or exerting energy in water over 90°F, your body temperature rises quickly and releases sweat.
Profuse sweating, as we all know, can lead to dehydration, cramps and muscle spasms.
So, what's the appropriate temperature?
Essentially, this depends on the age of the people using the swimming pool and the purpose for which it’s being used.
For example, small children and older people probably need the water to be a little warmer, while swimmers training for competition or exercising might prefer it a little cooler to keep from overheating.
Mayo Clinic suggests that it’s best to keep the pool between 83° and 88°F, taking into account the factors we just mentioned.
Take note!
Temperature & water quality
Now that you know the effect of water temperature on your swimming humans, you might be wondering if it really matters for the health of your pool.
Well, guess what? It does!
The main chemical you should be (and probably are) using is chlorine. Chlorine is the most effective agent for killing off harmful bacteria and algae in your pool.
But there are a number of factors that can decrease chlorine’s effectiveness, causing you to spend more time and money replenishing it.
Heat is one of those main factors. The higher your swimming pool water’s temperature, the more quickly the chlorine molecules are being consumed.
Temperatures consistently above 90°F can lead to scaling and algae overgrowth.
Because not only do warm temperatures break down the chlorine, but algae loves warm water and tends to set up camp in these conditions.
Types to choose from
So, what’s a pool-owner to do?
Well, invest in a pool thermometer of course!
It's a cheap and easy way to help keep your pool chemistry levels regulated while maintaining comfortable swimming conditions for your family.
There are two types to choose from: digital and analog. So, which is better? You decide…
Digital
Digital models are the most popular types of thermometers because of their technology.
They display temperature either on a separate display console or with some models, even a smartphone app.
Analog
Analog models are just the basic types of thermometers your mom used to keep in her medicine cabinet that use mercury to show the temp.
Floating and hanging types can be either analog or digital, but handheld thermometers are always digital. So, what’s the difference? Let’s see…
Floating
Floating models float on the pool surface and measure the water temperature with sensors inside of the unit.
They can be slightly less accurate than other types because they are not completely submerged underneath the surface and will pick up part of its reading from the air surrounding it.
Hanging
Hanging models are usually attached to the side of the pool or the ladder and are submerged a few inches under the surface of the water.
These can be digital or analog and usually give a fairly accurate reading as the temperature is taken from sensors completely submerged under the surface.
Handheld
Handheld models are usually held in your hand like a gun and an infrared laser is directed at the water to give a temperature reading.
These are considered pretty accurate as well.
Shopping tips
There are a few factors to consider when choosing the best thermometer:
Display
A thermometer won’t do you much good if you have too much difficulty reading it to know what it means.
And each display is different: some are different sizes and brighter backlighting.
It’s best to ask an associate to let you try one out or check out the display before you decide, especially if you have vision problems.
In addition to just being able to read the display, you need to decide if you'd also like to have a wireless version with a display you can keep inside.
Although not necessary, it is sometimes very convenient to be able to monitor this if you're waiting for it to heat up so you can swim.
Battery
How is the thermometer powered?
Analogs don’t need batteries, but digital models will require some type of power source.
If you'd rather not mess with batteries, but prefer a digital kind, look for a solar-powered version.
If you don’t mind batteries, it’s still a good idea to find out what type it uses.
Keep in mind that button, or watch batteries are sometimes more expensive, harder to find and harder to install than AA or AAA batteries.
Accuracy
Obviously, there's not much point in using a thermometer if its readings are inaccurate anyway.
Buy the best quality unit you can afford and check online reviews to back up your decision.
Also look for reading frequency and supported channels.
Durability
Some cheap thermometers just aren't made to hold up to extreme conditions or long-term use.
So unless you want to replace it on a regular basis, look for one that is known for its durability: you can do this by checking online reviews.
Most people who purchase these products are all too happy to let readers know how long they lasted and how they held up.
Also, try to purchase pool products from well-known and respected companies in the pool industry.
You can usually tell who these are from the size of their product line and the amount of reviews they have.
And it doesn’t hurt to buy products that come with a longer than normal warranty; this is often an indicator that a company stands behind their product.
In addition to the above, here are three other features to consider when shopping:
7 best pool thermometers
The HydroTools Digital Pool and Spa Thermometer by Swimline (click here to check the price on Amazon) is a solar powered, floating model that features an easy-to-read LCD display, and comes with a handy nylon cord to secure it to your ladder.
It comes with 2 AA batteries and is priced pretty competitively compared to other thermometers.
The Ambient Weather WS-14 (click here to check the price on Amazon) is waterproof, water resistant, and simply floats on the top of your pool while the temperature is wirelessly transmitted to its console.
It also monitors air temperature in both Fahrenheit and Celsius so you can decide how warm or cool the water needs to be.
What’s really unique about this one is that it has an 8-channel switch so you can monitor the temp from multiple locations, including your indoor temperature.
This analog thermometer from Milliard (click here to check the price on Amazon) is designed with a cute little frog on top so the kids love it.
It’s also got a rope tether so you can tie it to the side of the pool to keep it in place.
Customers like it because it stays afloat without tipping over, which can be a problem with devices that are unequally balanced.
This analog unit from Aquatix (click here to check the price on Amazon) is built to last with sturdy plastics and waterproof fittings.
Its large print makes it easy to read and easy to use, and it reads up to 100 degrees fahrenheit.
It's simply designed, stays afloat and easy on the budget.
The only common complaint with this one is that the tether string is a little flimsy.
The Milliard Sinking thermometer (click here to check the price on Amazon) is a little bit different in that it’s made to intentionally sink a little below the surface instead of float.
Some people prefer this for a more accurate reading of the body of water that isn’t affected by external conditions like sunlight and wind.
It’s made durably and sensibly and is super easy on the budget.
Consumers say the string could be a little longer, but were able to remedy that by adding some length.
We like anything solar powered because of its ease of maintenance.
This floating digital thermometer from Swimline (click here to check the price on Amazon) displays the accurate temperature right on the top of it.
It’s very simply designed, extremely inexpensive and made of durable materials (shatter resistant).
Consumers like it because it’s large numbers make it easy to read and there are no external displays or devices to set up.
The Raytek Infrared Thermometer (click here to check the price on Amazon) is fun to use because it looks a little like the speed scanners police officers use.
The way these work is that you can target any area of your pool spa, and jacuzzi and the thermometer gives you an instant reading in large digital numbers. All without touching the water!
It’s a little bit pricey, but it’s insanely accurate and incredibly innovative. Everyone in your family will love using this one!
Bottom line
Do you need a pool thermometer? In a word–yes.
Your pool’s water temperature can affect your swimmers, either creating a pleasant and comfortable environment or wreaking havoc on their muscles.
And it also affects the health of the water, creating either a breeding ground for bacteria or a haven of clean swimming.
Choosing the best swimming pool thermometer doesn’t have to be difficult either.
If you struggle with technology and just want to start with something simple, choose one of the analog models we suggested here.
But if you’re ready for a more advanced product and are ready to go to the next level, try a digital version with all the bells and whistles.
Either way, this handy little instrument is a cheap way to help keep everything in balance and your family swimming comfortably all season.
Hi, I’m Matt Harper, the founder of poolcareguy.com, a site I started with one simple mission: to help people around the world clean and take care of their pools and hot tubs on their own, without the hassle.
I’m not a professional pool cleaner and don’t have any formal training, I’m just an average guy who loves hanging out by his pool and hot tub and taking care of it. After many years on the job, I’ve become quite good at it.
On this website I will be teaching you absolutely everything I know about pools and hot tubs.