Love it or leave it, chlorine has been the number one product for swimming pool sanitization for decades. It by far does the best job of eradicating bacteria and algae but it comes with a lot of baggage like red stinging eyes, faded swimsuits, dry itchy skin and premature wear and tear on equipment and surfaces. So below is a quick tutorial on how you can use chlorine as safely and effectively as possible.
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Follow Label Directions
Chlorine comes in a variety of different forms from gas that is injected by professionals to liquid bleach that can be poured directly in the pool. More commonly used is tablet or granular chlorine but it is important to know how to use these. See the chart below.
Chlorine comes in a variety of different forms from gas that is injected by professionals to liquid bleach that can be poured directly in the pool. More commonly used is tablet or granular chlorine but it is important to know how to use these. See the chart below.
Types of Chlorine | Form | % of Available Sanitizer | pH of the Product | Used in the following way |
Dichlor | Granular | 56% or 62% | 6.9 | Hand fed or through feeders |
Tri Chlor | Tablets/Granular | 90% | 2.9 | Through feeders |
Calcium Hypochlorite | Tablets/Granular | 65% - 70% | 11.8 | Hand fed |
Sodium Hypochlorite | Liquid | 12% - 15% | 13 | Hand fed |
Lithium Hypochlorite | 35% | 10.7 | Hand Fed | |
Household Bleach | Liquid | 6% | 13 | Poured into pool |
Gas Chlorine | Gas | 100% | below 1 | By Professional |
Need Help? Ask the Water Care Experts 800-222-0169
The level of chlorine in the pool is directly related to two factors:
The level of chlorine in the pool is directly related to two factors:
1. How much chlorine is being added to the pool? This is a function of the type of chlorinating system you have, what setting it is on and how often your pump is running.
2. What is the chlorine demand on the pool? Demand is the combination of all the things that use up or burn off chlorine including swimmers, sunlight, rain, water temperature, organics like bugs and leaves and other air borne chemicals like fertilizers.
How to Solve High Chlorine Levels
If your chlorine demand is low (not many of these things occurring) but you are putting in chlorine 24 hours a day, chances are you will have too much chlorine in the pool. If the chlorine level in the pool is higher than 3.0 ppm follow the steps below to reduce the chlorine in the pool.
- Turn off any chlorine feeder or generating device and wait for chlorine level to drop – DO NOT SWIM IN WATER OVER 5.0 PPM
- Consider your pump run time. If running 24 hours with a feeding device you are pumping chlorine into the pool 24 hours a day. Most pools do not need this much circulation and can be monitored with a simple timer. Smaller pools (under 15,000 should start at 8 hours and increase if needed while pools from 15 to 25 should start at 12 hours)
- Make sure whatever chlorinating device you have is not over sized for your pool size and how often you use it. Smaller pools that are used infrequently need systems that do not put out as much chlorine.
- Consider a low chlorine solution like our FROG Mineral Systems.
How to Solve: Not Enough Chlorine
If your chlorine demand is high (many of these things occurring) but you are putting in chlorine just a few hours a day, chances are you will have too little chlorine in the pool. Especially check fertilizers as these are nitrate based which consumes chlorine very quickly. If the chlorine level in the pool continuously stays lower than 0.5 ppm, follow the steps below to increase the chlorine in the pool.
1. Make sure your feeder or floater has chlorine tablets and increase the dial setting on your feeder or generating device. Test the water daily to until the chlorine level rises and stablizes.
2. Consider your pump run time. If running just a few hours each day, it may not be enough circulation for your pool which means your feeding device does not have enough hours to pump chlorine into the pool each day. Consider a simple timer to monitor the hours run. Smaller pools (under 15,000 should start at 8 hours and increase if needed while pools from 15 to 25 should start at 12 hours)
3. Make sure whatever chlorinating device you have is not under sized for your pool size and how often you use it. Larger pools or pools with frequent use need systems that put out more chlorine than systems for smaller pools.
4. Consider an alternative pool care method like our FROG Mineral Systems.
