Why Your Pool’s Water Level Matters—And How to Maintain It

Let’s imagine that you’re hosting a pool party, and you’ve gone all out: you’ve got the right food to grill, a playlist ready to go, and extra-flashy inflatable pool toys to keep the energy high. But at the last minute, you realize with a sinking feeling: you didn’t actually invite any swimmers. Sort of like a bad dream, right? Well, when it comes to pool maintenance, not checking your water level is kind of like that unbelievable error. Checking your level couldn’t be easier to do, and feels like a no-brainer once you have it on your radar. But it’s also one of the most essential parts of keeping your pool running. Without it, that safe swim is just not going to happen.

So yes, checking your pool’s water level is another maintenance step you’ll need to add to your routine. But it’s also incredibly effortless—and at the end of the day, there is just no other way. I’ll explain what your pool’s water level is, where it should be, what can happen when it’s off the mark, why it is often the heart of pool maintenance problems, and how to maintain it. This couldn’t be more important, so let’s get to it.

Hold On. What’s a Pool’s Water Level? 

This one is simple, so no need to get out your notepad—or your arsenal of chemicals. Although you might be familiar with sanitizer levels, your pool’s general water level doesn’t refer to what’s in the water at all. It just refers to how full your pool is. (Some pool experts might also refer to this as your waterline—especially if your pool has a nasty stain where the top of your water rests against your pool walls.)

The chemical makeup of your water will always matter. But in this case, we’re just talking about volume. Because although it’s important to maintain your sanitizer, pH, and all those other superstar liquids you balance every week, it’s equally essential to maintain how much water is in your pool. We’ll get to exactly why in a sec. 

Where Should My Water Level Be?

Here’s some good news for you: it just doesn’t get more straightforward than this. As you probably know, all pools are unique as far as their size—that’s why it’s important to calculate how many gallons your pool contains in order to outfit it with the right equipment and amount of chemicals. But you won’t need to do any algebra for this one.

No matter what your pool size is, your water level should be halfway up your skimmer plate. Just to remind you, your skimmer is the rectangular opening that is built onto the size of your pool wall and connects to your greater circulation system. That means that water travels from your pool through your skimmer, through your pool lines, back to your pump and filter, and out through your return jets. And that entire system goes a lot more smoothly if your skimmer is only halfway full of water.

So what will happen if your water level isn’t halfway up your skimmer? We’ll break that down next, but get ready for some horror stories—and not the axe-wielding kind. These awful outcomes? They can be totally avoided by one weekly glance.

Do you have a variable-speed pool pump yet—and the lower monthly energy bills to show for it? The Blue Torrent 2 HP Variable-Speed Pump is the one to try—it’s ultra-powerful, allows for more thorough circulation, is eligible for rebates, and pays itself off in under a year in energy saved. As customer Dave Schmidt says, “My pool has never looked cleaner. I am pleased with my new pump!” 

What Happens When the Water Level is Too High?

Alright, let’s say that you followed your well-intentioned but unaware builder, and you topped off your pool water for the summer. (This happens a lot!) Other than hitting halfway up your skimmer, your pool covers your skimmer entirely. Hey, more water, more pool. What’s the harm in that?

In order to understand why your water should never be over halfway up your skimmer, we also need to cover the filtering out that your circulation system can do—as long as it’s properly supported. If you skim your pool’s surface daily, as recommended, with a net on a telescopic pole, you know about how many leaves, twigs, and other junk land in your pool on a daily basis. But you also don’t see it all. This is because when your pump is on, your skimmer is sucking in water from your pool—and a ton of debris along with it.

If your pool’s water level hits halfway up the skimmer, the debris that is floating along in your pool water is filtered out into the skimmer basket, which looks like a strainer in a bucket that is built into the ground beside your pool. That’s why it’s important to clean this skimmer basket out every day.

If your water level is too high, whether because your builder told you to top off your pool or because you didn’t cover your pool before a major storm, a bad chain of events will happen. The skimmer won’t be able to suck in that floating debris, so all the junk will stay in your pool, exhaust your sanitizer, make your swim less safe, and lead to more expensive chemical costs and time-sucking maintenance needs.

So now we know we don’t want our water level too high. But what about when it drops down below the recommended level?

It won’t matter that you cover your pool if the weight of rainwater pushes that nasty water right into your pool anyway. Keep your cover light and secure with the BLACK+DECKER 800 GPH Automatic Pool Cover Pump, which detects up to a quarter inch of rain and works on its own—fast. According to customer Christy Williams, “The little pump is very quiet. I can’t even hear it running.”

What If My Water Level is Too Low? 

Now this is what you really, really don’t want to let happen. Although what will occur is fairly simple, the long-term outcomes of having a water level that below halfway up the skimmer can be complicated—and all pretty terrible.

If your water level is too low, your skimmer will suck in water as usual, but it will also suck in air. And in case you don’t already know, your pool system was designed to move water only—never, ever air. It’s one of the reasons that it’s important to prime your pump on pool opening day every spring.

When air enters your circulation system, it will cause your equipment to work overtime. This means that your pool pump can heat up—and in some cases, even melt. That’s an expensive tool to go kaput, and it’ll off-balance the rest of your equipment and chemicals virtually immediately—not to mention, spike your energy bill. Remember, every working part of your pool depends on the fact that the pool pump is run for the right amount of time every day (generally, that’s about eight hours). It can also add pressure to your filter, cause your lines to stop working, and wreak general havoc on every part of your circulation system. Basically, you don’t want this to happen. You just don’t.

Troubleshooting? Check Your Water Level

Next time you’re trying to sort out just what is going wrong with your circulation system, your water level should be the first thing you check. Make sure it’s halfway up your skimmer—not above, and not below. Here are three reasons why you should check your water level before doing anything else.

It’s a Common Cause

Are your return jets suddenly weak? Is your pump waking you up at night with a ridiculously loud noise? Is your pump too hot to touch? The list goes on, and in most cases, your water level could be the culprit. This is especially true when your waterline is too low, because air has a way of moving through its own path of destruction when it is introduced into your greater circulation system.

It’s Effortless to Check

It’s convenient that your water level should be the first thing you check. For example, unlike having to check your pool pump for clogs, you don’t need to power your system down or open any machines up. You’ve just got to stand on the side of your pool and eyeball how high your water reaches. If that’s not effortless, I don’t know what pool maintenance work is. 

It’s (Often) Easy to Fix

When your water level is too low, it’s as easy as throwing a garden hose into your pool and cranking it on. Done and done. It’s a little more of a hassle if your level is too high—but that’s also less likely to happen. In either case, I’ll show you how to maintain your water level on an ongoing basis, as well as how to fix it if it’s off. 

How to Maintain Your Pool’s Water Level—In Three Steps 

So now we’re on the same page about why your water level matters. But how to keep it on the mark—and avoid all the awful damage an incorrect level can cause? I’ll show you how to nail it in three steps, including how to lower and raise it when you need. Let’s do this.

1.     Eyeball It Once a Week

Sure, things can go terribly wrong if your water level is off. But thankfully, your waterline probably isn’t going to change very dramatically overnight—most of the time. Some factors that can influence your water line quickly are major storms, extremely hot weather that causes your water to evaporate at a higher rate, and a high swimmer load (especially if they’re big splashers, or competing to make the biggest cannonball).

Most of the time, checking your pool’s water level should be on your weekly pool maintenance routine. If one of the above events has happened, you should check it a little more frequently—but remember, your pool contains thousands of gallons of water, so your level will be more stable than you’d probably expect. 

2.     Draining Water—The Right Way

The most common reason why your water level would be too high is totally preventable—and that’s a good think, since you’ll need to drain your water to fix your level. That common reason? You probably guessed it: heavy rainfall.

Not only does covering your pool for the storm take less effort, but it also protects your water chemistry from getting seriously wacky thanks to the rain. Rain, after all, has a different pH than your ideal levels for your pool, and can sometimes introduce algae spores into your water. No, thanks. Just make sure that you choose the right cover pump for you—before that storm hits.

Now that your pool is getting drained, are you noticing that it’s a lot filthier than you thought? It’s time to give your automatic cleaner a much-needed upgrade by switching to the Blue Torrent MyBot Inground Robotic Cleaner, which works powerfully on its own to keep your walls and floor sparkling clean. As customer David Lain says, “Very pleased. My wife loves it.”

3.     Adding Water—And Keeping It Balanced

Let’s say your water level is below halfway up your skimmer. Yikes. Do not go on that grocery run, do not watch that show, do not do anything else before addressing your water level. But despite the urgency, the job you have ahead of you is far from tough. Simply turn on your garden hose, throw it into your pool, and wait. Once your waterline is halfway up the skimmer, you just need to rebalance your chemicals and you’re in the clear.

A little stressful, sure. But totally worth it, when the alternative is buying a new pool pump and/or needing to prime it to get all that destructive air out of there.

Keep It Level! 

Now you know one of the most essential aspects of keeping your pool sparkling clean with equipment that’ll last for the long haul and waters ready for swimmers. Now you’ve got your work cut out for you, but the best part is this: checking your water level is going to be the easiest part of your maintenance routine. Gives a whole new meaning to the phrase “eyeball it,” right? And for now, everything is in tip top shape—thanks to you. Enjoy.


Related articles:

Ideal Schedule for Your Variable Speed Pool Pump

What To Do When Your Pool Pump Won’t Turn On?

How To Fix An Overheating Pool Pump?

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