The first option for testing uses a liquid chemical OTO (orthotolidine) that causes a color change to yellow in the presence of total chlorine. You simply fill a tube with water, add 1-5 drops of the solution, and look for the color change. This method does not measure free chlorine.
Free chlorine refers to both hypochlorous acid (HOCl) and the hypochlorite (OCl-) ion or bleach, and is commonly added to water systems for disinfection. Total chlorine is the sum of free chlorine and combined chlorine. The level of total chlorine should always be greater than or equal to the level of free chlorine.
Furthermore, why is there no free chlorine in my pool? This occurs when too much stabilizer is added to the water or when the swimming pool isn’t being partially drained and refilled periodically. Chlorine lock can also occur if the pH is unbalanced. If you have a free chlorine reading of 3 and a total chlorine reading of 7, there is a problem.
Accordingly, how do you increase free chlorine?
Add enough chlorine to bring the Free Chlorine count to reach the Break Point Chlorination Level. Repeat steps 1 & 2 until Break Point Chlorination level is reached or until: The combined chlorine level of your pool drops under 0.5. An overnight Free Chlorine test shows of 1.0 ppm or less.
What does OTO test for?
OTO (Orthotolidine) Test OTO is a solution that turns yellow when added to chlorinated water. The darker it turns, the more chlorine is in the water.
What happens if free chlorine is low?
When the chlorine level is too low, microorganisms like bacteria are able to multiply faster. With harmful bacteria like e-coli, this will quickly cause your pool to be unhealthy, risking any swimmers potentially getting sick. Algae growth. Algae will also grow quickly.
What if free chlorine is low?
Things that cause low free chlorine levels are excessive sunlight, high bather loads, and improper water chemistry. Not having enough chlorine in your swimming pool will also cause the little bit of chlorine that’s in there to be used up faster too.
What is free chlorine in your pool?
Free chlorine is the type we commonly test to determine the proper chlorine levels in pool water – this is the amount of chlorine that is still available to sanitize your water. Free chlorine is the chlorinated water that has not interacted with any contaminants in the water.
What should free chlorine level be?
In general, the free chlorine level should remain between 1.5 and 2.5 parts per million. Combined chlorine levels should not be above 0.5 parts per million, and swimmers are likely to be more comfortable if the level is below 0.2 parts per million.
What is free chlorine in hot tub?
Free chlorine is the chlorine that isn’t combined with anything. If you neglected the tub and have stuff growing in it then you may need to shock the tub with 10 to 15 PPM free chlorine to kill the growing stuff and have a residue in it. Now combined chlorine is the chlorine that has bonded with the stuff it worked on.
What does free chlorine mean on a test strip?
In effect, free chlorine is the amount of chlorine that is free to kill harmful microorganisms in your swimming pool’s water. The easiest way to check your chlorine levels is with test strips. However, ideal free chlorine levels are dependent on cyanuric acid levels.
Does pool shock raise free chlorine?
Chlorine based pool shock (Calcium Hypochlorite) has a high pH, and will naturally raise the pH level of your swimming pool water, in addition to changing your chlorine level. Chlorine free shock has a neutral pH, and will not affect any of your pool chemical levels.
What is a free chlorine test?
Free Chlorine is the type that we commonly test for to determine the proper chlorine levels in pool water. Free Chlorine is also the chlorine that is still available to sanitize your water. Combined Chlorine is the chlorine that has already been “used up” sanitizing your water. And Total Chlorine is the sum of the two.
Will Shock raise chlorine level pool?
Raise the Level of Pool Chlorine 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.
Can you over shock a pool?
Start off by adding 3 or 4 gallons, and if you see no results overnight, add 3 or 4 more gallons the next day. Continue this process until you notice the water changing color to either cloudy white, light green or clear. YOU CANNOT OVER SHOCK A POOL ! The more you add, the quicker it will clear !
Does adding chlorine increase pH?
Using liquid chlorine raises the pH of the water. Liquid chlorine does not raise pH. When added to water, liquid chlorine (which has a pH of 13) makes HOCl (hypochlorous acid – the killing form of chlorine) and NaOH (sodium hydroxide), which raises pH. So the net effect on pH is zero (or almost zero).
How often can you shock a pool?
Always make sure that the filter system is running while shocking the pool. Some pool owners choose to shock their pools once every 1-2 weeks as normal maintenance. This is a great way to keep your chlorine level up and prevent algae growth.