As you have discovered, proper pool maintenance is a balancing act of all the chemicals necessary to keep the water safe for your family. Plus, all the terms used can be confusing, too!

In this article, you will learn about one of the common pool terms you may have heard: Total Dissolved Solids (TDS). We break down what the term means, how to determine if your pool suffers from high TDS, how to reduce it, and some prevention techniques.


The Answer to the Question “What Are Dissolved Solids?”

Total dissolved solids (TDS), refers to the measure of everything that has ever dissolved in your pool water, both helpful and not-so-helpful. It includes the byproducts of every pool chemical you’ve ever added, plus dissolved dust, dirt, pollen, algae, suntan oil, makeup, perfume, sweat, debris that falls into the pool, and even flecks of skin.

Over time, the levels of TDS increase, due primarily to normal water evaporation from the pool. The water level goes down and the solids stay behind, building up to higher and higher concentrations as you add more chemicals. Sometimes, the water you put into the pool has natural solids, too, which adds to the problem. A high TDS level can lead to cloudy or smelly water, eye irritation, and rashes.

The obvious question to ask next is, “At what point do these solids become a problem?”

The optimum number of Total Dissolved Solids in freshwater pools is up to 2,500 ppm (parts per million), while saltwater pools support higher levels of up to 5,000 ppm. Any readings above these numbers are a problem and need to be addressed. 

Before we discuss how to resolve high TDS levels, let’s examine other signs of high TDS in your pool.


Signs of a High Total Dissolved Solids Level

Maintaining your pool’s water chemistry is always a balancing act, but it becomes even more difficult when the Total Dissolved Solids level is high. The water in the pool becomes saturated with solids and new chemicals aren’t absorbed properly any longer. Put simply, your pool isn’t safe for your friends and family plus the conditions allow algae to form.

TDS too high | what are total dissolved solids | TDS

Here are some indications that your pool has a high TDS level:

– Faulty water test readings for other aspects of water balance.

– Difficulty maintaining correct water balance.

– Salty-tasting water.

– High calcium hardness levels.

– Scale buildup. 

– Skin and eye irritation.

– Algae growth despite good sanitizer levels.

– Cloudy or discolored water.

– Metal corrosion. 

So, if you have determined these symptoms are a result of high TDS levels, how do you attack the problem?


How to Reduce Total Dissolved Solids

Unfortunately, it isn’t as easy as heading to your pool supply store and buying a product or a chemical to lower this concentration of solids in the water. Keeping in mind what causes this problem to begin with, there is only one way to reduce the total dissolved solids in your pool. You will need to partially drain the pool and refill it with fresh water. 

Drain and refill one foot of water at a time. Keep checking the water until the dissolved solids drop to an acceptable level. You will need a meter designed for measuring TDS levels; standard test kits and strips that you use for measuring other elements of water chemistry don’t test for Total Dissolved Solids. The meter measures the volume of dissolved solids in the pool by testing the electrical conductivity of your pool water. So, don’t drain your pool completely. Drain only as much as you need to bring the levels of TDS to acceptable levels.


Prevention of High TDS Levels

Prevention is key. The various chemical treatments you add to the water regularly must continue. But, you can take some steps to reduce the other, more problematic solids accumulating in the pool, including:

– Requiring swimmers to shower before entering the pool and the pool area. 

– Skimming the pool regularly to eliminate leaves, grass, and other organic debris.

Vacuuming the pool regularly.

– Being careful with food around the pool.

– Testing for TDS often.

You can save yourself a lot of time and water by preventing many solids from getting into the pool water at all.

preventing high levels of total dissolved solids | what are total dissolved solids | TDS


Pool School Videos Can Help You Maintain TDS Levels, Too!

Total Dissolved Solids (TDS)–everything ever dissolved in your pool water–is inevitable. However, there are ways to lessen the impact of all the organic and inorganic solids on the water in your pool. Adding fresh water to the pool is one way, but at some point, the levels of solids must be lowered, too. And, just like with your own health, the health of your pool’s water depends on proactive actions to prevent the ill effects of foreign matter on the water.

Pool School Videos can show you exactly how to properly maintain your pool with less effort and save money, too. This includes helping you ensure that the level of total dissolved solids, as well as vital chemicals, are always in optimal range! 

We’ll help you become a pro at pool maintenance with 20 in-depth, self-paced videos like you won’t find anywhere else. These videos teach you how to properly maintain your pool to ensure it stays clean and safe for your family and are all available for an affordable one-time fee.

Pool School Videos was created by pool professional Mike Steele, aka “The Pool Doctor”. Mike has over 30 years of experience in professional swimming pool maintenance and his goal is to make pool care as simple and effective as possible. After you buy the video series, you will also become a member of our private Facebook group that provides personalized guidance. Simply post your pool-related questions and Mike will answer them within 24 hours. 

Get started today and save hundreds of dollars on pool care each year with the help of Pool School Videos!