Sign in to follow this  
Followers 0
Seahunt

How Long Does It Take Liquid Chlorine To Circulate

10 posts in this topic

I know the answer depends on several factors. I am trying to get my chlorine level right using liquid chlorine. How long after I add it can a get an accurate chlorine reading?

22k Gallons

Plaster pool

1HP pump with two return jets, two skimmers and two deep end floor drains

Added the chlorine slowly over the deeep end return jet.

Thanks!

Share this post


Link to post
Share on other sites

The conservative rule is to test after an hour, but in a pool with good circulation most of the chlorine is disbursed in around 10 minutes and the chlorine level doesn't change after around 20 minutes. I've done this sort of test in my own 16,000 gallon pool with 3 returns, one skimmer and two floor drains. I've also done dye tests that show chlorine getting distributed fairly quickly. So I think that testing after 30 minutes would be more than adequate unless you know your pool has circulation issues.

It does not take one turnover of water to get the chlorine mixed because circulation through the filtration system is not necessary for mixing. It is the stirring up of the water from the return jet flows that does most of the mixing, though initially the chlorine gets from the deep end to the shallow end primarily by going through the skimmer and floor drains through the circulation system and out all of the returns including those in the shallow end.

Share this post


Link to post
Share on other sites

Wow. Awesome, you are right. I added 96oz Chlorox and two hours later my chlorine had gone up 2.5ppm (basically what the pool calculator said it would). Thanks for the help. Now if I could just get my automatic chlorinator set correctly, I wouldn't have to play these games :D . Oh well, keeps me off the streets.

Thanks again.

Share this post


Link to post
Share on other sites

Use 1 gallon of liquid chlorine for each 10,000 gallons of water in the pool to provide a shock chlorination treatment. Perform a shock treatment of chlorine to your pool once each week.

Share this post


Link to post
Share on other sites

Use 1 gallon of liquid chlorine for each 10,000 gallons of water in the pool to provide a shock chlorination treatment. Perform a shock treatment of chlorine to your pool once each week.

In a properly managed pool, why would you want to shock it every week?

This is a legit question. I manage my own pool, and for the last two seasons I have used the BBB method, and according to the Pool Calculator it is always balanced, and maintaining it has been smooth sailing.

Share this post


Link to post
Share on other sites

I am curious as well. In my 20K inground Hydrazzo pool after 3 weeks of heavy use from 2 kids and their friends, my TC and FC levels are even, and I just add some bleach or mur. acid every day or 2 to keep pH around 7.4-7.6 and FC around 1-2. So far I have not seen a need to shock, though I suspect I will eventually. I would be curious what others have to say about their criteria for shocking the pool.

Share this post


Link to post
Share on other sites

Use 1 gallon of liquid chlorine for each 10,000 gallons of water in the pool to provide a shock chlorination treatment. Perform a shock treatment of chlorine to your pool once each week.

You can't make a blanket statement like this since liquid chlorine is commonly available in 6%, 10% and 12.5% strengths!

Also, the CYA level in the water has a direct influence on how high the FC needs to be raised to 'shock'.

Finally, If FC is at the proper level for your CYA, there is less than .5 ppm CC, there is not cloudiness or algae, and no strong chlorine odor (which there won't be if CC is below .5 ppm) then there is NO need to shock.

Share this post


Link to post
Share on other sites

Waterbear - I appreciate your clarification.

If I am using 6 or 12% bleach, how do I shock? Or is it better to use the stuff they sell at the local pool dealer, i.e. the powder that says 1 pound per 10K gallons?

Share this post


Link to post
Share on other sites

Waterbear - I appreciate your clarification.

If I am using 6 or 12% bleach, how do I shock? Or is it better to use the stuff they sell at the local pool dealer, i.e. the powder that says 1 pound per 10K gallons?

The powder sold by pool dealers/stores is usually a chlorine compound such as Calcium Hypochlorite (Cal Hypo), Di-chlor or Trichchloro-s-triazinetrione (Trichlor) and adds substantial amounts of either calcium or cyanuric acid (CYA) to the water right along with the chlorine. Excessive calcium or CYA can lead to problems with cloudiness and scaling (cal-hypo) or maintaining sanitation levels (Dichlor, Trichlor).

When shocking for algae, it's better to use liquid chlorine (10-12.5%) or 6% bleach because these add only a very small amount of salt in addition to the chlorine. The key to both effective daily sanitation and shocking is to have the right amount of Free Chlorine in the water based on CYA level (aka stabilizer or conditioner level). Refer to this chart for recommended minimum, maximum and shock levels for chlorine. Shocking consists of quickly elevating chlorine to the target (shock) level and KEEPING it at that level by frequent additions of chlorine over several days (testing, adding, testing, adding...) until the pool is clear, combined chlorine (CCs) are <= .5 PPM and there is less than a 1 PPM drop in Free Chlorine (FC) from dusk to dawn. It's much easier to perform shocking with a FAS-DPD chlorine test (part of Taylor's K-2006 kit).

Share this post


Link to post
Share on other sites

Waterbear - I appreciate your clarification.

If I am using 6 or 12% bleach, how do I shock? Or is it better to use the stuff they sell at the local pool dealer, i.e. the powder that says 1 pound per 10K gallons?

I prefer liquid chlorine in most cases but there are times I would select cal hypo or dichlor under specialized circumstances. (Cal hypo is easier to transport in larger quantities if I know I am going to need a LOT of chlorine and cost is not a major factor--it is easier to carry several 1 lb bags around than several gallon jugs! If I need to raise CYA while trying to clear a green pool then dichlor will do both at the same time without worrying about filter issues.)

As a rule of thumb, I use liquid chlorine or bleach since in most areas of the country it is the most cost effective and has the fewest side effects. One gallon raises 10k gal about the strength of the chlorine (i.e. one gal of 6% raises 10k gal about 6 ppm).

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!


Register a new account

Sign in

Already have an account? Sign in here.


Sign In Now
Sign in to follow this  
Followers 0