Keep Water Clean

Keeping Your Water Clean

As you probably know, the occasional addition of new water -- or wholesale water replacement in the case of spas -- isn't enough to keep the water clean and clear of unwanted and often microscopic contaminants.

But worry not! Pool and spa chemists have spent years developing a variety of tests and chemical-treatment methods to keep your pool and spa safe and sparkling clean.

Your goals here are water sanitation and water balance. In other words, you want your levels of sanitizers (such as chlorine or bromine) and your levels of pH, total alkalinity, water hardness and total dissolved solids to all fall within acceptable limits.

And learning to keep these areas in check isn't as complicated as it may seem. To simplify things, we'll explain the relevant topics one at a time.

Sanitizers

Sanitizers, or disinfectants, are hardworking chemicals. They also have a killing streak in them -- which is exactly what you want.

The important thing to keep in mind is, that for them to do their duty, they have to be present in the pool and spa water at all times. There always needs to be a certain minimum amount -- called a residual -- of sanitizer in your water.

What we're saying is, to make sure your pool and spa are protected from bacteria and their friends, you need your sanitizers on 'round-the-clock duty.

When you add your sanitizer, therefore, you should be adding enough to kill any existing contaminants in the water -- and create a residual that can neutralize any dirt, debris or germs that may get into the water before you next treat it.

That said, let's take a look at some of the most common sanitizing chemicals and equipment available on the market today.

Chlorine

Chlorine has been somewhat of a wonder drug for pool and spa environments. It has the power to kill bacteria and algae -- and works extremely well in aqueous environments.

Chlorine is not invincible, however. Like most chemicals, it has a threshold -- a point at which it has used up all its sanitizing power and can no longer protect your pool and spa water.

Chlorine levels are also heavily influenced by evaporation, splash out and destructive UV rays, not to mention a low pH. (You'll read about this last factor in more detail below.)

Once added to the water, the "free available" chlorine -- that portion of the chlorine with the killing power -- will sanitize and oxidize the water by attacking undesirables such as bacteria, algae, sweat and oils from your skin, residual soaps, shampoos, perfume and, yes, urine.

As it uses up its killing potential, the chlorine becomes ineffective or it combines with the contaminants and remains in the pool and spa water in the form of chloramines.

FYI: It is the chloramines in your pool and spa water -- not too much "good" chlorine -- that causes a chlorine-like odor and can irritate your eyes and skin.

Indeed, when a pool or spa exudes a chlorine odor and you begin to hear complaints of skin and eye irritation, that is a loud warning that there is not enough chlorine in the water. If this is the case, you should test the water and add the appropriate amounts of sanitizer as soon as possible. (Check out the Testing Your Water section to learn more about this process.)

The recommended level of free available chlorine to keep in your pool is between 1.0 and 3.0 ppm or parts per million. For spas, the recommended level of free available chlorine is between 1.50 and 3.0 ppm.

(For the definition of parts per million and other pool- and spa-related terms, see the Glossary of Terms section).

Another note: We'll address how you measure chlorine and other water-balance levels in another section.

Chlorine is extremely susceptible to sunlight and needs to be regularly monitored. But just as we use sunscreen to protect our skin from the sun, chlorine uses a sunscreen of cyanuric acid. Used this way, cyanuric acid is also commonly called a stabilizer or conditioner.

With its help, chlorine retains its effectiveness. Without going into the chemical whys and wherefores, know that acid works to help keep a fairly consistent chlorine level (a residual) in the water.

Some chlorine-based sanitizers are sold with a dose of cyanuric acid already mixed into the product. One such product is trichlor tablets, which are usually placed in a floater, chemical feeder or in the skimmer basket. Another commonly used product is sodium dichlor, which is a granular substance usually dispersed directly into the pool or spa water, or added via the skimmer.

Bromine

Also available on the market today is a chemical sanitizer called bromine. Do note, however, that bromine cannot be stabilized with cyanuric acid. As much as 65 percent of a bromine residual can be depleted by the sun in a two-hour time period. Because there is no known way to retain a reliable level of bromine when exposed to sunlight, many experts recommend it for indoor pools or spas only.

FYI: The acceptable range of bromine for your pool or spa is from 2.0 to 4.0 ppm.

Bromine also has no odor, and dispensing it your spa via a feeder allows it to dissolve at a slow, constant, desirable rate. Just be sure to remove the feeder when your spa is in use.

A final note: When using bromine as your sanitizer, you will need to occasionally shock the water with large doses of another chemical to oxidize waste material still in the water. (We'll explain this in more detail below.)

Alternative Sanitizers

Although chlorine and bromine are the most commonly used sanitizers, there are a few alternatives available to also consider. One such alternative is a chlorine generator.

Wait, we just discused chlorine! How is this product different?

The liquid or granular chlorine most people are familiar with is added directly to pool or spa water or dispensed through a feeder or similar automated system. Chlorine generators, conversely, actually create chlorine in the pool or spa without you having to measure out any chemicals.

These generators are electrical devices that manufacture chlorine from salt added to the water. The resulting chlorine gas is then put directly into the water through the circulation system.

Chlorine generators create a residual, which can be tested with a DPD or OTO test kit. (These test kits are described in more detail in a later section.)

Another alternative sanitizing source is ozone. No, it's not just the atmospheric layer that protects us from the sun's harmful rays. Rather, the ozone used in pools and spas is a modified version of that gaseous oxygen.

To its advantage, ozone works quite well as a sanitizer and an oxidizer. . Because it is a form of oxygen, ozone doesn't last long in an aqueous environment. Once it does its job of ridding the pool and spa water of bacteria and other unwanted matter, the ozone then reverts back to oxygen and either dissolves into the water or escapes into the air.

Because it cannot create a residual, an ozonator must be used in conjunction with small amounts of chlorine or bromine -- how much chlorine or bromine depends on how long the ozonator is run each day.

One other common kind of sanitizing equipment is an ionizer. This system introduces silver and copper into your pool or spa water through the circulation process. It works well as a sanitizer but does require the addition of an oxidizer.

Oxidizers

OK, you've been reading about oxidizers and oxidizing -- and still have no idea what they are or what they do. Let's find out.

Oxidizers work with sanitizers to rid your pool and spa water of pollutants. By definition, sanitizers kill things like algae and bacteria but they work very slowly and inefficiently when trying to remove waste products such as sweat, skin oil, shampoos, soap and urine. This is where you need separate oxidizers.

Oxidizers destroy these undesirables. They do their part by breaking down the contaminant's structure, rendering them vulnerable. The sanitizers can then attack and kill the organisms.

Some products, such as chlorine, act as both a sanitizer and an oxidizer. Bromine, on the other hand, does not oxidize very well and therefore needs the aid of a separate oxidizing chemical to properly clean your pool and spa water.

The marriage of sanitizers and oxidizers is an almost foolproof method of keeping invaders out of your pool and spa water.