Keeping your pool water balanced is crucial to having a safe and healthy swimming environment.
And it’s not as simple as just making sure you have chlorine.
If any factor is out of whack, it can throw the others off, making your pool a hospitable place for all kinds of nasty bacteria and annoying algae.
What you'll need to get started
Importance of balanced pool water
Like I said earlier, keeping your water chemistry balanced is how you keep it safe for swimmers and bacteria and algae-free. But let’s look at it a little closer.
You will use some type of sanitizer in your pool water. That’s what keeps it...well...sanitized.
And usually that sanitizer is chlorine. But it’s not enough to just throw some chlorine tabs in the dispenser or pour some solution in the pool.
You have to know how much chlorine is already there, how much to add, and when to leave it alone.
You can actually get too much chlorine in your pool. When chlorine levels are too high, it can cause skin and eye irritation and in extreme cases, even chlorine poisoning.
Chlorine poisoning can cause symptoms such as nausea, burning throat, itchy eyes, difficulty breathing and chest pain.
But aside from keeping the proper levels of chlorine in the pool, all the other levels have to stay balanced in order to help it do its job.
The pH level might be the second most important chemical to balance because it also directly affects how well the chlorine works.
>>Read: How to lower pH in your pool
If it’s too low, the chlorine will work well, but the water becomes corrosive, damaging equipment. It can also cause skin and eye irritation because the water is acidic.
And each level affects the other, either hindering it or boosting it too high.
So, keeping them all in the proper ranges is the only way you can keep your pool safe, clean and damage-free.
Using your test kit
Every test kit comes with its own set of instructions, and they will vary some in the way you read them and their color spectrum. But basically, for liquid kits, this is how you will use them:
- 1Dip some water out of your pool. Your test kit will come with some sort of water collector. It’s usually a plastic container that holds water in the middle and has numbers on the side that will give you a reading of the levels.
- 2Add reagent. The kit comes with a reagent that you add to the water. Your kit’s instructions will tell you how much to drop in.
- 3Cover the vials. You will then use the caps that come in your kit to cap the vials close and gently turn upside down a few times to mix the reagent with the water.
- 4Read the results. This can be the tricky part. Your test kit instructions will give you the colors that you are supposed to match. The color your water turns in the vials indicates the level of your chemicals.
Chemical factors to test
Once you’ve gotten the hang of how to read your test kits, you need to know what you are looking for and how to balance them.
A pH level is how acidic or base your water is. It’s an unstable factor that is affected by the other factors as well as debris, rain and algae.
The higher the levels, the more base the water. The lower the levels, the more acidic.
If your pH levels are too low, your water can cause skin and eye irritation from the acid and it can start to cause your pool liner and other pool equipment to erode.
The proper ranges for pH levels are between 7.4 and 7.6. Anywhere above or below that can become hazardous to the pool and to swimmers.
If your pool testing kit indicates that your pH levels are out of whack, you will need to add the proper pH balancing chemical to get it back to normal.
If it’s too low, you can add either sodium carbonate or sodium bicarbonate (baking soda) to raise it.
There are also chemicals on the market like pH Up that is made for this.
It may be helpful for you to use this since it has easy-to-follow instructions that will tell you how much to add in any given situation.
If your pool’s pH levels are too high, you can add muriatic acid or sodium bisulfate. The are usually labeled as pH Reducers.
They too will have simple instructions to help you get your levels back in safe range: simply follow them until your pool water tests within normal range again.
Alkalinity is kind of a mediator for the pH levels.
Since pH is such an unstable factor, it needs a stable alkalinity level to keep it steady.
If alkalinity is too low, the pH levels will be all over the place. It it’s too high, it kind of locks the pH in a bad range and makes it hard to adjust it.
Alkalinity levels should stay between 100 and 150 ppm.
If they are out of balance, it's usually because they are too low, so you will need to add sodium bicarbonate to raise them.
But if for some odd reason, they are too high, muriatic acid or pH reducer should do the trick.
This determines how hard or soft your water is. But it’s more important than you think.
Sure, if your water is too soft, it can leave your skin feeling slimy and unclean.
But aside from that, it makes your water hungry for calcium, so it seeks it out, consumes it, and starts to cause corrosion on your pool’s surface and equipment.
To raise your calcium hardness, you can use calcium chloride.
To lower the levels, muriatic acid should help.
The recommended level for calcium hardness is 150-400 ppm.
Chlorine can get confusing.
There is free chlorine, which is the chlorine that is still available to clean your pool.
Combined chlorine is what has already been used up.
And total chlorine is the sum of the two.
The measurement you'll use to determine how much sanitizer to add to your pool is mainly the free chlorine level, which is what most test kits will test for.
But to make sure it is working effectively, you'll need to make sure your free chlorine is higher than the combined chlorine levels.
Ideal chlorine levels are 1.0-3.0 ppm.
If your chlorine levels are too low, you'll usually add chlorine according to the manufacturer’s instructions to bring it back up.
If it’s too high, the best thing to do is wait for it to go down naturally.
Also, make sure no one gets in the water when the chlorine is too high.
Cyanuric acid is a chemical compound used to stabilize your chlorine.
It acts as kind of a sunscreen, keeping the sun’s UV rays from disintegrating it too quickly.
It’s also called CYA or pool stabilizer and it comes in liquid or granules, and is sometimes included in the chlorine tabs you buy.
It’s an important chemical to use because without it, the sun will destroy about half your chlorine in less than thirty minutes.
But there is a proper balance for it: if it gets too high, it can cause your chlorine to stop working completely.
Cyanuric acid levels should stay somewhere under 100 ppm. I usually say about 50 ppm is good and not to worry too much about it unless it does start to creep over that 100 mark.
What about pool temperature?
It might seem weird to think that water temperature will affect your pool chemicals, but remember that bacteria and plant life usually thrive in warm environments.
So algae and other nasty stuff likes to get in your pool and multiply where temperatures are too high.
And when this happens, chlorine tends to be used up more quickly trying to kill it off. It will also start to affect the other chemicals and throw everything out of balance.
Of course, no one wants to have to break a sheet of ice to jump in the pool either, so it’s best to keep the temp at a comfortable, safe level by regulating and monitoring your pool heater: ideal pool temps are between 77° and 82°F.
What about the saturation index?
The saturation index, or Langelier Saturation Index (LSI), is used to “determine the tendencies of water toward corrosion or scaling based up on the pH of calcium carbonate.”
It’s basically a system of measurement that is used by some people to make sure the water maintains the most perfect balance possible.
The formula is SI = ph + TF + CF + AF - 12.1.
Now, am I telling you to do this?
Well...if you're kind of a chemistry geek and really like playing with numbers like these, then knock yourself out!
It could help save your pool from ANY issues.
However, it's labor and time-intensive and most pool owners don’t pay much attention to it, including me.
But now you know what it means and why people talk about it!
Keeping your pool water balanced is the most important job you'll do as a pool owner and you should be checking your levels at least once a week.
But if any of the levels are off, you may be checking them daily until you get them balanced.
If you just hate the thought of messing with chemicals and reading charts, then feel free to hire someone to do it or take your water samples to your local pool supply store.
Do yourself a favor, though, and try doing it yourself first.
You'll probably be amazed at just how easy it is!