Frequently asked questions

Browse the topics below for answers to questions pool and spa owners have encountered.

For help with a specific question, you can call our free helpline at 1-800-SOS-POOL (767-7665).

Pool and Spa Water FAQ

> Can I use pool products for my spa, or vice versa?
We don’t recommend it. The chemical processes work the same, but dosage amounts and the concentrations in our products are formulated for either pool OR spa use. For instance, in some products the chemical concentration in may be significantly higher in the pool product, than in the equivalent spa product.
> How long do I have to wait after adding algaecide before I can use my spa or pool?
After the algaecide is added, you should wait 15 to 20 minutes before going in. Be sure to test your water for chlorine and pH levels, so your pool or spa will be safe and comfortable for your users. Kem-Tek algaecides are not toxic to humans.
> Why did my water change color after adding chlorine, and how do I clear it up?
Chlorine reacts to metals in pool and spa water to produce colors such as green, yellow, orange and brown. These metals may be present in the source water you use to fill your pool or spa, or can occur when pool or spa water has low pH levels. Try Metal and Calcium Eliminator [text link to product page] for pools, or Stain and Scale Inhibitor [text link to product page] for spas, to lock up the metals in your water so they can no longer react to chlorine or bromine.
> How do I clear persistently cloudy water?
Check your filter for leaks, misaligned components and/or pin holes in filter surfaces. Test your water for pH; a pH level above 8 can create cloudy water especially if water has not been refreshed on a regular basis. Early-stage algae growth can also be a factor; algae can contribute to cloudy water after chlorine treatment.
> How do I adjust total alkalinity?
Total alkalinity can be increased with an alkalinity booster, or lowered with acid to the original level of alkalinity. Note: all Kem-Tek products that increase alkalinity also increase pH, and vice versa.
> Why does my chlorine level keep dropping?
Chlorine is inherently unstable and will break down over time. This process is greatly accelerated by algae growth, exposure to strong sunlight (the use of cyanuric acid slows this process significantly), elevated water temperatures, the amount of pool or spa use, and having low pH in your water.
> Why does algae keep recurring in my water?
Algae can only be fully removed by killing it all at once, so small or incremental treatments don’t eliminate all the algae or prevent it from coming back. To stop it from coming back, you need to add enough chlorine or algaecide to your pool or spa water to overwhelm and kill all of the present algae.

Pool Care FAQ

> How often should I test my pool water?
Test chlorine levels every 1-2 days. Test for pH levels on a weekly basis. Test for hardness and total alkalinity monthly. Test for cyanuric acid (also known as stabilizer or conditioner) twice a year.
> When is the best time to shock my pool?
The best time to shock your pool is during the evening, when it is not in use, so the chlorine can be applied without interference. For faster treatments and a quick chlorine boost, you can use Shock Quick 10 [text link to product page] at any time of day and you can use the pool just 15 minutes after applying. Important note: Be sure to follow all the instructions on the product.
> How soon can we use our pool after adding Kem-Tek products?
For most products sold by Kem-Tek, you can use the pool 15 minutes after application, as long as your pump system is operating properly, and your pH and chlorine levels are good. An important exception: When you need to shock your pool and the chlorine is increased to more than 5 parts per million (ppm). When this is happening, wait until the water is at 3 ppm or lower before adjusting or letting anyone back in the pool.
> Why did my pool water turn cloudy after adding pH Plus?
Cloudy water is the result of dissolved pool surface particles (tiny amounts of plaster and metal) which solidify when the pH of the water is raised to 7 or higher. The dissolving of pool surface particles occurs when the pH is below 7, and this can cause particles to accumulate. Try Water Clarifier [text link to product page] or Ultra Clarifier [text link to product page] to settle the particles so they can be easily removed by a vacuum.
> How do I get rid of algae in my pool water?
Unless all of the algae present are killed in one treatment, it will continue to reappear. High doses of chlorine and other chemicals -- sometimes doubling or tripling the usual amount for pool treatments -- are necessary to eliminate all of the algae. The more aggressive the treatment, the more likely you will succeed. A important safety note: Once the dosage exceeds what is required for your pool, your pool may be out of service for several days until the chlorine drops below 3 parts per million (ppm).
> Can Kem-Tek products be used in my salt-water generator pool system?
Yes. All Kem-Tek products are compatible with salt water generator pool systems.
> How do I start up my above-ground pool?
First, fill your pool and test the pH level of the water, adjusting the pH as needed until you achieve a pH level of 7.2 to 7.6. Shock the pool to 5 parts per million (ppm) chlorine, and then use your preferred Kem-Tek product to add chlorine daily to maintain optimal chlorine levels.

Spa Care FAQ

> I was told not to use chlorine with bromine in my spa. Is this accurate?
Not entirely. The active ingredients for brominating tablets are bromine and chlorine, with most being about 39.2% available bromine and 44.4% available chlorine. What you DO NOT want to use is any chlorine tablets or any chlorine with calcium hypochlorite in the active ingredients. Never put two different chemicals in any floater, feeder or dispenser.
> If I am using bromine in my spa, do I also need to use chlorine?
Yes. With regular use of your spa, the bromine will be used up rapidly and cannot keep up with the sanitation needs of the spa. Using a spa every day with two or more people makes it almost impossible to maintain sanitation with bromine only. Bromine is used in spas because chlorine is fast dissolving and will not hold up to heat. Bromine is heat resistant. So it is best to you use bromine and chlorine together to keep your spa clean and sanitized. Shocking the spa water after use will destroy micro-organisms and contamination in the water, which then lets the bromine build back up.
> I have an ozonator. Do I still need to use chlorine and bromine in my spa?
Yes. An ozonator introduces ozone into the water, destroying micro-organisms and contamination. The ozonator only works on low speed and, therefore, is introduced into the water at certain intervals. Ozone is very fleeting and only is effective on the water passing thought it, with no residual effect. Once the ozonator is shut off, there is no continuing sanitation. Most spa manufacturers recommend using a backup sanitizer system, (such as bromine), to provide sanitation when the ozonator is not operating.
> What causes foam in my spa?
Foam is often the result of water imbalance, organic material, or the presence of growths. Try keeping the pH level between 7.2 and 7.6 along with shocking weekly, to help prevent this problem. You may need to shock at two or three times the normal dosage to get rid of pesky foaming problems.
> I adjusted the pH in my new spa, but the next day it was high again. How can I fix this?
Freshly-filled spas often have a very high acid demand. Be patient. When you first fill a spa, it takes about one week of adjusting the pH level each day before the pH becomes balanced, because freshly filled spas typically have a very high acid demand. As long as the pH level is above 7.0, the spa can be used while lowering the pH.
> The pH in my spa will not lower. Why?
To get the pH down in the spa you need to add 1 ounce of pH Minus [text link to product page] for every 100 gallons of water. Do this every 20 minutes with the spa running. Check the pH and add more as need to get the pH level to 7.4. The harder your water is the more pH Minus [text link to product page] it will take to get the water adjusted for optimum pH level.
> When testing my spa for chlorine/bromine or pH I get color for a few seconds, then it turns clear, or orange flakes appear. Why?
This is due to a really high chlorine or bromine level. Remove any floating dispensers you are using. This will allow the chlorine level to come down. Do not use your spa until the water chlorine level is at or below 3 parts per million (ppm), or the bromine level is below 6 ppm.
> How do I lower my bromine levels in my spa?
You need to remove the floater and let sunlight get to the spa. Or you can drain out part of the water and add new water.
> Why is my spa pH reading a bluish-purple color?
This is a false pH reading due to high bromine. You need to remove your bromine floater and remove the cover, to let as much sunlight as possible to get to the water. If your spa is indoors, you will need to drain out about half the water and refill with fresh water.
> Why do my spa walls feel gritty?
High water temperature can cause minerals to deposit on the walls of your spa. To remove it, scrub spa walls thoroughly and then treat your water with Stain and Scale Inhibitor [text link to product page] to prevent future buildup. High pH levels in your water can accelerate the process, so it is important to maintain a pH of 7.2 to 7.6 in your spa water. If neither of these methods work, it might be necessary to drain and replace the water in your spa.
> What do I need to start up my spa?
When you first fill a spa, test your water for pH level. Then adjust the pH levels using pH Minus [text link to product page] to LOWER a HIGH pH level, or pH Plus to RAISE a LOW pH level. Then shock the spa with either Liquid Shock [text link to product page] or All-in-One Chlorinating Granules. [text link to product page] Then if you are using bromine, put in the floater with bromine tablets in your spa. If your source water has high metals content, you may need to use Scale and Stain Inhibitor [text link to product page] before you add other products to prevent yellow or green water from occurring.