Swimming Pool FAQ

Click on the questions below to display the answers to these common questions about swimming pools.

Why is my liner wrinkled?

Wrinkling of Vinyl Pool Liner

Our vinyl manufacturer has invested a great deal of time and money into discovering the causes of and the prevention of wrinkling. Wrinkles that develop in swimming pool liners after installation are caused by the vinyl absorbing water and thereby changing dimensions. Testing has shown that high levels of chlorine or bromine will initiate excessive water absorption into the vinyl liner and lead to wrinkles. Low pH and cyanuric acid stabilizer are also factors in wrinkle formation because the activity level of the chlorine is affected by pH and stabilizer level.

Our experience has shown that the use of trichloroisocyanuric acid sanitizer (Trichlor) and low pH levels can cause wrinkling of your vinyl liner. Alkaline sanitizers (Hydochlorite) and non- chlorine sanitizer systems have been found to be safer to use with vinyl liners


Does alkalinity affect the pH?
Total Alkalinity

Alkalinity is a measurement of the alkaline materials dissolved in water. Alkalinity in the ideal range of 100 to 150ppm helps the pH to resist fluctuations. If the alkalinity is low it can cause a "pH bounce" causing the pH level to fluctuate in and out of the acceptable range.


Why is my liner white and chalky?

Water Chemistry

Proper water balance is the single most important factor to maximizing the life and appearance of any swimming pool. The following table shows ranges for basic water chemistry.

Factor Range Test Frequency
pH 7.2-7.6 Daily
Free Chlorine 1.0-2.0 Daily
Total Alkalinity 80-120 ppm Weekly
Calcium Hardness 200-300 ppm Monthly
Stabilizer 35-60 ppm Monthly

PH Levels

PH is the measurement of acidity of water - measured on a scale of 0 to 14 with 7 being neutral. A pH below 7.0 means the water is very acidic, as the pH approaches 8.0, the water becomes very basic (alkaline).

Not only do proper pH levels allow the other chemicals to do their work, but it is important to note that low and high levels can cause damage to a vinyl liner. Under the right circumstances with pH below 7.0, the liner can actually grow and develop unsightly wrinkles. High pH greatly accelerates the aging process and shortens the life of the liner.

Chlorine is much less effective at higher pH levels. At a pH of 8.0; chlorine is only 22% effective.

How do I clear up my cloudy pool water?
Cloudy Water

Contaminants buildup: When swimmer wastes and other contaminants build up, the result is "combined chlorine". Shock the pool!!!

Chemical residue: Using a calcium hypochlorite shock such as (*Shock *Sock-It *Shock-it *Burn Out *Break Out) can result in a residue build up and cloudy water. If the water looks like chalk or milk, it is usually the result of using a lot of calcium hypochlorite shock. To use this type of shock, especially in vinyl liner pools to prevent bleaching of the liner, you must:

  • Fill a bucket about 1/2 full of water
  • Add Shock - do not stir - let sit for a few minutes - pour only the liquid into the pool
  • Discard the residue
  • Do not try to dissolve the residue

Water Out of Balance: A high pH, high Total Alkaline or High Calcium Hardness will cause cloudy water. Test the water!!

Algae: Algae is a possible cause of cloudy water.

Poor Filtration: Is the filter system running a significant number of hours every day? During the swim season, the filter needs to run a minimum of 10 to 12 hours daily.

Pools with cloudy water or algae.

  • Adjust pH to 7.2-7.6
  • Add algaecide
  • Add shock
  • Add flocking agent
  • Run filter 1 hour - turn off & leave off overnight
  • Next day vacuum to waste

Metals: The presence of metals in the water such as iron (reddish-brown), copper (blue-green) or manganese (brown-red) can cause cloudy water. To remove the metals:

  • Add 1 quart flocking agent
  • Add 1 quart Majestic Blue
  • Run filter 1 hour; turn off overnight
  • Vacuum to waste
  • When pool is completely clear, add a stain & scale preventer to remove any stains



How did the metals get in my pool?

It is not uncommon to find metals, often called free metals, dissolved in pool water. Usually they come from source water, sometimes they come as a result of the erosion of metal pool fixtures, such as heater cores.

Free metals in pool water can cause staining of pool surfaces and inhibit the performance of water sanitizers. Ideally, there should be no metals in the water: 0 ppm. If metals are detected in your water you will need a sequestering agent to render them harmless.

In which order should I adjust ph and alkalinity?
Adding Water Balance Adjustment Chemicals

It is best to pre dissolve a water balance adjustment chemical in a plastic bucket of pool water. Then add to the deep end of the pool or in front of a return with the pump running.

  • pH Adjustment: Add recommended dosage, wait several hours and test water again.
  • Alkalinity: Add at the rate of 5 lbs or less; wait about 10 minutes between each 5 lbs.
  • Hardness: Add at the rate of 5 lbs. Or less; wait 30 minutes between each 5. If large amounts of calcium are needed, add over several days.
Low pH and High Alkalinity Adjust Alk first - Next Day pH
High pH Low Alkalinity Adjust pH first - Next Day Alk
Low pH and Low Alkalinity Adjust pH first - Next Day Alk
High pH High Alkalinity Adjust Alk first - Next Day pH
Do I need to stabilize the chlorine?
Chlorine Stabilizer (100% Cyanuric Acid)

Stabilizer acts as a sun shield to extend the life of chlorine up to 3 1/2 times. It actually holds the useful form of chlorine in the pool water until needed giving longer protection against bacteria and algae. It leaves no residue - 100% soluble. "Stabilized" chlorine products (sticks - tablets - chlorine powder) contain some cyanuric acid which helps to maintain the proper level throughout the season.

What types of algae are out there and how do I treat my pool if affected?

Mustard Algae - Common algae in pools appears yellow-brown or "mustard" colored. It brushes off the walls of the pools easily, but quickly returns. It often rows in shady areas with poor circulation. It resists chlorine and shock treatment.

Solution - Use an algaecide along with chlorine shock. Follow label directions. Place all vacuum equipment - hose, head, pole, brushes, etc. into pool during treatment Maintain a higher than normal chlorine reading for 4 to 5 days after treatment.

Green Algae - Green algae is one of the most common problems for pools. It usually appears in corners or other areas where circulation is poor. Once established, green algae can grow explosively.

Solution - Use Algaecide along with chlorine shock.. Follow label directions. It is also recommended to use a flocking agent, always vacuum to waste or drain (not backwash).

Black Algae - A very resistant form of algae that clings to the pool's walls, floor, and cracks. The longer black algae are present, the longer it will take to get rid of it. Black algae can actually pit the mar cite finish in a gunite pool. Treat black algae as soon as it is detected. Black algae are usually found in gunite/concrete pools.

Solution - Brush algae spots vigorously with a stiff algae brush and pour algaecide along the sides where spots are visible. Run filter continuously for one hour, and then add chlorine shock to the pool. Turn off filter and leave off for several days.

Preventing Algae
WEEKLY Brush walls and pool floor
WEEKLY Vacuum pool
WEEKLY Use a maintenance dose of Algaecide
WEEKLY Use a maintenance dose of Majestic Blue
DAILY Maintain a proper chlorine reading
WEEKLY Keep properly balanced - recommended readings:Free Chlorine:1.0-2.0, pH:7.2-7.6, Total Alkalinity:80-120ppm, Hardness:200-300ppm, Stabilizer35-60ppm


Why do I need to shock my pool?

Pool water composition always includes some undesirable elements that actually contaminate the water and reduce the efficiency of the disinfectant or sanitizer. Material such as hair spray, suntan oil, cosmetics, perspiration and other organic material react to combine with the chlorine in the water to form "combined chlorine". Once "combined chlorine" forms, it acts as a very poor disinfectant, contributing to eye and skin irritations and the forming of unpleasant chlorine odor. Pools with this problem are often inaccurately accused of having too much chlorine.

Routine shock treatment is necessary to destroy combined chlorine compounds and restore the chlorine sanitizer to "free chlorine" efficiency. A pool can be shock treated by adding large doses of chlorine, commonly referred to as super chlorination, or by adding a non-chlorine shock.

My pool has a very strong chlorine odor. Is there too much chlorine in my pool?

No, you don't have enough "free chlorine" in your pool. Most pools contain both good chlorine and bad chlorine. The good chlorine is called free chlorine and is capable of killing germs. Bad chlorine, on the other hand, is called "combined chlorine" and is a poor germ killer.

Too much combined chlorine in your pool causes the strong chlorine odor. When the combined chlorine level reaches 0.2 ppm or more, it is time to shock your water. Shocking will eliminate the odor.

When I shock my pool, should I use chlorine or non-chlorine shock?

Both treatments accomplish the goal of destroying and removing bather waste and preventing the formation of combined chlorine.

Super chlorination, the addition of large amounts of chlorine, has some drawbacks. Because it requires large amounts of chlorine, it can damage liners and swimsuits and upset water balance. Additionally, it is difficult to determine proper dosage amounts and it requires swimmers to wait until the level of chlorine drops, often a day or more, until they can swim.

Non-chlorine shock, on the other hand, does not require excessive chlorine use and allows swimming almost immediately after application, does not harm liners, has easily determined dosage rates and does not upset water balance.

Do I need to add a sanitizer regularly?

>Yes, an E.P.A. registered sanitizer should be added and maintained at proper levels at all times. Non-chlorine shock treatments contain no chlorine, therefore you must make regular additions of sanitizer to ensure that you are disinfecting the water.

I have heard of people talking about pink algae. What is that and how do I treat it?

Pink algae is not an algae at all, but a bacteria. Normal algaecides will not reliably work on them. There are products that are designed to assist chlorine with removal of these bacteria. To eliminate pink algae, you must super chlorinate your pool, turn off the filter, and clean it with a good filter cleaner. Let the filter soak overnight then backwash to waste. Let the chlorine level subside before using again. (Hint: a good rule of thumb is to toss into the pool the equipment that is normally used for pool maintenance, including hoses, brushes, etc. prior to super chlorinating. These need to be disinfected too).

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