Sunlight Affects Chlorine
The bright sun breaks down the chlorine and you'll notice your pool chlorine levels drop. ... Your pH levels affect your chlorine levels and the ability for the chlorine to do its work properly. If your water's pH is too high, it hinders the chlorine's ability to efficiently clean the pool.
To properly maintain the water chemistry in your swimming pool, put chlorine tablets in a floating chlorine feeder, and once a week, add 3 lbs of shock to the pool at night. The next morning, add algaecide to the pool. Use test strips twice a week to monitor the levels of the chemicals.
Look for algae. Algae growth in your pool will rapidly consume free chlorine. High temperatures, high levels of phosphates, dirty or clogged filters and low chlorine levels can promote algae growth. Scrubbing with a brush can remove algae from surfaces if they have accumulated in one place.
When you're shocking a pool, the goal is to raise the free chlorine level of the pool water to roughly 10 times the combined chlorine level.
The addition of a cyanuric acid stabilizer to pool waters treated with chlorine is necessary to protect the active life of chlorine and its derivatives in the waters from the damaging effects of the sun's ultraviolet (UV) rays. When exposed to UV rays, chlorine evaporates rapidly.
Chlorine has a low pH level, and in order to maintain your pool water's clarity and balance, shocking weekly will allow you to quickly raise the chlorine level, which will rid the pool of contaminants, without lowering the water's pH levels.
Raising pool chlorine can be much easier than trying to lower chlorine levels. Simply adding chlorine in the form of chlorine tablets, granular chlorine, liquid shock or powder shock will increase the total amount of chlorine within the pool.
In short, the UV rays produced by the sun have a major effect on chlorine. When exposed to UV rays, chlorine ions begin to separate, which eventually destroys them. And as your chlorine burns away, your sanitizer level drops. This is the very reason why CYA (cyanuric acid), or chlorine stabilizer, exists.
The Effect of Sunlight on Chlorine: Degradation and Reduction. As little as two hours of sun exposure — that's all it takes to reduce chlorine content by 90%. ... However, because the sun's UV rays break it down, the chlorine turns into a gas. This gas then rises into the air instead of mixing with the pool water.
Total chlorine is simply the combination of free and combined chlorine. Shocking then releases the combined chlorine and off-gasses the contaminants, increasing the amount of free chlorine in your pool or spa.
Waiting to swim after shocking. Follow package instructions, which will guide you in how long to wait after shocking before swimming. Heavy shocking with granular chlorine will generally require 24-48 hours before the chlorine level has dropped to safe swimming levels (below 5 ppm).
A chlorine level of between 3-5mg/l must be maintained in your hot tub at all times. The addition of chlorine will depend upon usage and bathing habits. It could be daily or every 2-3 days (for 1mg/l add 2g per 1000 litres).
Daily as needed and indicated by measurement. One caveat, however: if your total alkalinity and pH are not where they should be, you will find it difficult to keep enough free chlorine in your pool water. Adjust your alkalinity first, then correct your chlorine.
The Bottom Line about Pools and Chlorine
As mentioned above, you could probably swim in a pool without chlorine without any major health issues. However, long-term use of a pool lacking chlorinated H2O could make you sick or, at the very least, contribute to rashes and other types of skin irritation.
Baking soda, also known as sodium bicarbonate is naturally alkaline, with a pH of 8. When you add baking soda to your pool water, you will raise both the pH and the alkalinity, improving stability and clarity. Many commercial pool products for raising alkalinity utilize baking soda as their main active ingredient.
RECOMMENDATIONS TO MINIMIZE WATER LOSS
The number-one way to combat evaporation is with a pool cover. It's estimated that a pool cover will reduce evaporation by 95 percent. Solar covers can heat your pool in the off-season, too. A pool cover reduces the pool's chemical consumption and reduces your cleaning time.
Depending on its levels of content, the evaporation time for chlorine from tap water can be estimated: 2 ppm of Chlorine will take up to 4 and a half days or around 110 hours to evaporate from 10 gallons of standing water.
If the water is clean and clear, then add about 3 oz of liquid chlorine per 1000 gallons of water – while the pool filter is running. This should give you a chlorine level of about 3 ppm.
Extreme pH changes can also affect how the chlorine works in your pool. Chlorine works most efficiently in water with a neutral pH level between 7.4-7.6. If the pool is too alkaline, or more than a pH of 8.0, the efficiency is less than 20 percent.
The best chlorine neutralizer available for swimming pools is still sodium thiosulfate.
But excessive exposure to chlorine can cause sickness and injuries, including rashes, coughing, nose or throat pain, eye irritation and bouts of asthma, health experts warn. Instructions for safely chlorinating a pool usually call for a maximum of four parts per million when people are in the pool.
A pool filter should be run for a minimum of 6 hours after shocking a swimming pool. This is to allow the filter to clean the water and give the shock enough time to fully mix with the pool water. Running the filter after shocking for 24 hours to 7 days is necessary if the pool has a large amount of algae.
Liquid chlorine and granular shock have the same active chemical that sanitizes your pool, what changes is the strength and the way you use it. Liquid chlorine is less costly, unstabilized and comes in liquid form. Granular shock is stabilized and comes in a solid form that dissolves in your pool.