Why is My Swimming Pool Cloudy? Causes and How to Fix It

Is your pool looking a little hazy lately? Cloudy pool water is one of the most common problems Austin homeowners face, especially during our hot, humid Texas summers. Between the high heat, heavy use, and unpredictable rainfall, it doesn’t take long for even a well-maintained pool to turn dull and cloudy.

At Aqua Clear Pool Care, we help Austin pool owners restore that perfect, sparkling-blue clarity. Here’s why your pool might be cloudy and what you can do to fix it fast.

• Check your filtration system and make sure your pump runs 10-12 hours a day.
• Test and balance pool chemistry (chlorine, pH, alkalinity)
• Clean or backwash your filter to restore proper flow.
• Shock the pool to kill bacteria & any oxidize contaminants.
• Adjust for environmental factors (rainwater, pollen, debris).
• Try a pool clarifier for quick results on minor cloudiness.
• Call Aqua Clear Pool Care if cloudiness persists after 24-48 hours.

Several factors can cause cloudy pool water, especially in Central Texas’s unique climate. Here are the most common causes:

Your pool pump and filter work hard to keep your water clean. If your pool is cloudy but your chemicals test perfectly balanced, your filtration system is likely the culprit. If your system isn’t running long enough each day (we recommend 10–12 hours in Austin’s warm months) or your filter is clogged, debris and fine particles can build up quickly. The longer your pool pump work, the more your water is getting filtered. If you are worried about your energy bill, switch to a  variable speed pump and take advantage of the $300 rebate of Austin Energy.

As a general rule, there should be at least 1 hour of pool pump run time for each 10 degrees of outside temperature. This means, in the summer when it’s often over 90 degrees in Austin, that you should run your pump at least 10 hours during the day.

It’s very important to run the pump when it is hottest outside (not overnight).

Cloudy water with balanced chemistry almost always means your filter needs cleaning or your pump isn’t running long enough.

Austin’s hard water can make balancing your pool chemistry tricky. If your chlorine levels are too low or your pH is off, bacteria, algae, and minerals can cloud your water fast.

Keep your water balanced with:

• Free Chlorine: 1–3 ppm
• pH: 7.2–7.6
• Total Alkalinity: 80–120 ppm
• Calcium Hardness: 200 to 400 ppm
• Phosphate: less than 200 ppb
• CYA: 30 to 50 ppm

Shocking the pool with CAL-Hypo will increase the PH of the pool significantly. Shocking your pool could make it look very cloudy. Be sure to lower the PH with Muriatic Acid after shocking the pool.

Here’s Why:

If your pool is cloudy 24-48 hours after shocking, the problem is most likely caused by:

• High pH created by the shock treatment itself (especially with Cal-Hypo) — add muriatic acid to lower pH to 7.2-7.6
• Dead algae particles are too small for your filter to catch — use a clarifier or flocculant
• Dirty or undersized filter that can’t keep up — clean or backwash your filter
• Poor circulation — ensure pump runs 10-12 hours daily

Dry weather dust, Central Texas tree pollen, and body oils (or sunscreen) all make your pool water cloudy. And yes, rain can make your pool cloudy, too! When it rains heavily, your chlorine levels get diluted, your pH level goes down, and all that dirt and debris from your yard and the surrounding environment flows into your pool water.You’re likely to see your pool lose clarity after a big storm or a windy day. You’ll also likely have to rebalance your chemistry and shock your pool. Most Austin-area pools need something more than chlorine to be crystal clear all the time: algaecide, phosphate and enzyme removers are an absolute must in Austin. We like the CV 700 from Orenda Technologies and the algaecide from PoolRX.

We don’t mean to brag, but algae just loves Austin’s hot and humid weather (algae starts to grow in water when it is above 78 degrees). Even if you don’t see green, early-stage algae growth can cause your pool to look dull or cloudy. It is best practice to test the phosphate (algae fertilizer) regularly and add an algaecide to your pool to limit or eradicate algae growth.

How to Clear Up Cloudy Pool Water 

If your pool water is looking cloudy, here are a few quick steps you can take before calling in a professional:

Start with a quality test kit or bring a sample to a professional. Adjust your chlorine, pH, and alkalinity as needed.

A dirty filter is one of the fastest ways to get cloudy water. Rinse cartridges or backwash your sand or DE filter to restore flow.

A pool shock treatment kills bacteria and oxidizes contaminants that cause cloudiness. Shocking works best when cloudiness is caused by algae, bacteria or organic matter—but not if cloudy water is due to poor filtration or imbalanced pH. Run the pump for 24 hours after shocking, then retest your water chemistry.

Clarifiers group tiny particles together so your filter can catch them. It’s a quick fix for minor cloudiness but won’t replace proper filtration or chemistry.

Tired of Cloudy Pool Water? Let Aqua Clear Pool Care Fix It for You

If you’ve tried everything and your water still looks cloudy, it’s time to call
Aqua Clear Pool Care. We provide full-service pool maintenance in Austin, Texas, and surrounding areas. Our experienced technicians will:

• Test and balance your pool water
• Deep clean or service your filter with our filter cleaning service
• Eliminate algae and bacteria with our green to clean service
• Keep your pool looking crystal clear all season long with our weekly service

Whether you need a one-time cloudy water treatment or ongoing maintenance, we can do it all!