No Chlorine

  • 7.3K Views
  • Last Post 13 September 2016
ras5114 posted this 23 August 2016

I'm am having trouble getting enough chlorine in my pool this year. I'm in Michigan and it has been an unusually hot summer. (That's a good thing by the way!) All of my water chemistry is in balance except my chlorine. I can't get enough in the water to hardly register on either a dip stick or a liquid test kit. I have an automatic chlorinator that holds 12, 3" tablets. The pump is running fine and the chlorine is moving into the pool at about the expected rate. The water is crystal clear and I'm having no alge problems. PH looks good, stabilizer is in range and alkalinity is right where it should be. But no chlorine. The water has hovered right around 90 degrees most of the summer. I'm assuming it is just burning the chlorine out almost as fast as I get it in. I do throw a couple extra tablets in the skimmer once in a while just to try to push the levels.

Should I just leave well enough alone or is this something I need to be concerned with? I had a chlorine lock issue a few years ago and it was a pain in the butt to deal with not to mention extremely expensive. I hate to have to go through that process again if it's not necessary.

 

Any suggestions??

Order By: Standard | Newest | Votes
InyoRob posted this 23 August 2016

Hello Ras5114 - We recommend not letting the tablets get down to little pieces before you put new tablets in the chlorinator. When they get down to half the starting size, add more tablets.

What is the stabilizer level in parts per million?

Service posted this 23 August 2016

Hi Ras5114,

Please post your water test results as we will need these to determine what is going on. Also is there any visible signs of algae in the pool or other organic material like leaves? There are two things that consume chlorine... Uv rays from sunlight and organic material like algae or leaves. Your Stabilizer (cya) level is really important as it acts as sunscreen for chlorine, if your stabilizer is too low then the sunlight will quickly burn off your chlorine and if your stabilizer is too high then it will make your chlorine ineffective.

Thank You Patrick

Thank You

Patrick

www.inyopools.com

ras5114 posted this 24 August 2016

Thanks guys. I'll check the chemistry tonight and let you know the results. I normally try to keep the chlorinator pretty full. I don't let it get down to less than half before I fill it up again. With the heat we're having I fill it every couple of days. My pool is in an area with very few trees. Other than a few bugs it stays pretty clean.

ras5114 posted this 25 August 2016

OK, got the chemistry.

CA = 55ppm

FC= 0

TC = 1.2

CC (combined chlorine) = 1.2

PH = 7.2

TA = 35 - 40

I realize my TA is a little low. I added 5 pounds of increaser last night but didn't have time to get a good reading after adding it. I may need a little more. But I doubt that's affecting my chlorine levels.

InyoRob posted this 25 August 2016

The pH and alkalinty are low but it sounds like you adjusted the alkalinity. How often have you been shocking the pool with either liquid or granular shock? How much shock do you use? How many gallons is your pool? Does the free chlorine register after you shock the pool?

ras5114 posted this 25 August 2016

The pool is just over 23K gal. I haven't shocked very much this year. We haven't had much rain and the pool has been really clear. It also doesn't get a ton of use. Just my wife and I and an occational visitor. I have shocked about 4 times this summer. I use two bags each time. The chlorine level spikes after shocking but falls right back off after about a day.

PH is almost always low. For some reason, in our area it is really hard to keep the PH up. I add a lot of PH increaser over the year. I can get it up but it normally falls of over a couple of weeks.

InyoRob posted this 25 August 2016

Most one pound bags cover 10,000 gallons of water. We would recommend adding three bags of shock (cal-hypo) or 2.5 gallons of liquid chlorine (sodium hypochlorite). This will be the appropriate amount of shock for your pool. At that point the tabs should maintain the free chlorine level. 

If this doesn't work, let us know and we can recommend another method. That method includes eliminating tablets and only using liquid chlorine.

 

ras5114 posted this 25 August 2016

I'll give that a try.

thanks for your help!!

Service posted this 25 August 2016

I would agree with Rob I would shock and make sure your feeder is filled to the top with tablets and then test regularly for the next few days to see what happens with your Free Chlorine. Also are you seeing any visible signs of algae? Please post back your test results to this thread to keep us in the loop.

Thank You

Patrick

www.inyopools.com

ras5114 posted this 25 August 2016

Very little algae. I see a bit of "dead" algae that gathers around the corners and the seams of my liner but nothing in the water causing hazing. I use about 4oz of algicide per week just as maintenance. That seems to be working really well.

ras5114 posted this 08 September 2016

OK, so I've used three bags of shock and put it in after sunset to give it a better chance to work. I left the pump running all night and checked the chlorine levels the next day. Nothing. The Free Chlorine is registering virtually 0.

I've adjusted the alkalinity to about 60ppm. I've added some PH increaser to get my PH up but that always seems to be pretty hard to do. For some reason, in my area, everyone complains about not being able to keep their PH up. It's at about 7.0 right now.

Again, my pool has stayed the clearest it has ever been this season. I just can't register and Free Chlorine. I'm getting ready to close for the season in the next couple of weeks. Do I really need to worry about this or should I just close and start the battle again next season?

By the way, I need to order a closing kit. Any recommendations?

 

Service posted this 08 September 2016

Hi Ras5114,

Your combined chlorine of 1.2 ppm indicates that you do have live algae in your pool and this organic material is consuming your free chlorine. I would suggest putting in 6 bags of shock and then test again, you should at this point show a Free Chlorine reading and your Combined Chlorine should be below .5 I would suggest getting rid of the algae before closing as you will have a mess on your hands when you open in the spring. I would add the shock in the evening and test in the morning. Please let us know how this works. Just to wrap up we are looking for you to have a Free Chlorine reading in the morning and your Combined Chlorine to be below .5 ppm Ideally for closing you will be at 3 PPM Free Chlorine.

Thanks

Patrick

Thank You

Patrick

www.inyopools.com

InyoAlan posted this 08 September 2016

When reading your water chemistry levels, the one reading I did not see is the CYA or cyanuric acid level. What is the most recent test results for this level? I know we have been focusing a lot on the pH and Alkalinity levels, and for a vinyl liner pool, keeping the pH in a 7.4-7.6 range is recommended. Keeping the Alkalinity in a 80-100ppm range will help stabilize the pH levels. Keep in mind that the acidity level of the pool will fluctuate when shocking the pool. Here are a few suggestions:

1. If you see any algae bloom popping up in your pool, yellow mustard, black, or green algae, you will need to treat the pool and eliminate this bloom. You will need to superchlorinate your pool and add the correct algaecide to KILL the algae bloom. Having a previous algae bloom that was not killed properly could cause some of the issues you are having. What you would typically experience is low chlorine levels followed by hazy water and then a hint of the algae bloom. Shocking the pool gives the appearance of the bloom going away, but soon after the hazy water and bloom re-appear. Again, if this sounds like your issue, you will need to kill this algae bloom properly and then you will expect your chlorine levels to be maintain.

2. Low CYA (cyanuric acid or stabilizer) levels. This issue will allow the majority of your chlorine to dissipate quickly. This is caused by dilution of chemicals due to the constant addition of water/rain or from not using enough tablets to adequately chlorinate your pool. How many tablets are you using each week? During the summer for a 23,000 gallon pool, it is recommended to use 3-4 tablets per week. 

3. Heavy bather loads can cause a higher demand for chlorine. We would recommend using a Non-Chlorine shock (Oxidizing Shock) to assist in eliminating organic waste and to assist in freeing up your available chlorine after swimmers have been in the pool.

I hope this helps. Knowing that you are closing the pool down soon may tempt you to not put as much effort into  this. Just keep in mind that if you are able to solve this issue now, this may prevent a headache come next pool season. Good luck and let us know if we can help any further. 

Thank you,

Inyo Alan

ras5114 posted this 08 September 2016

Thanks Alan,

I don't see any algae bloom at all. This has probably been the first year I have not had to deal with hazy water. It has been crystal clear all year. I'll check on the CYA and let you know. We have a pretty minimal bather load so I doubt Non-chlorine shock would be an issue. In terms of chlorine usage, my chlorinator holds about 12 3" tablets. I go through somewhere between 3 and 5 per week depending on pool temp. It's been pretty hot this year so I'm using a bit more. I fill it once a week but will check on it mid-week on occasion and refill if necessary.

Service posted this 08 September 2016

Hi Ras5114,

I'm not sure if you saw my last comment but you may want to take the approach I suggested below

Thanks

Patrick

 

Hi Ras5114,

Your combined chlorine of 1.2 ppm indicates that you do have live algae in your pool and this organic material is consuming your free chlorine. I would suggest putting in 6 bags of shock and then test again, you should at this point show a Free Chlorine reading and your Combined Chlorine should be below .5 I would suggest getting rid of the algae before closing as you will have a mess on your hands when you open in the spring. I would add the shock in the evening and test in the morning. Please let us know how this works. Just to wrap up we are looking for you to have a Free Chlorine reading in the morning and your Combined Chlorine to be below .5 ppm Ideally for closing you will be at 3 PPM Free Chlorine.

Thanks

Patrick

Thank You

Patrick

www.inyopools.com

ras5114 posted this 08 September 2016

Thanks Patrick,

I did miss it. I'll try this tonight and let you know what happens.

InyoAlan posted this 08 September 2016

Ok, well please let me know when you have that additional information. I look forward to hearing from you.

 

Inyo Alan

Service posted this 10 September 2016

Hi Ras5114,

Did you add the additional shock? Were you able to get a free chlorine reading and did your combined chlorine drop below .5?

Thanks Patrick

Thank You

Patrick

www.inyopools.com

ras5114 posted this 12 September 2016

Hi Patrick,

Driving rain all weekend so I didn't get the shock in yet. Hopefully tonight.

I checked my CYA levels. About 80ppm.

Still having trouble getting my PH up. My test kit is showing yellow. No mater how much of the solution I use to check the demand, I can't get it to turn pink at all. I'm going to try to add some more PH increaser and see if that helps. I"m using your Taylor K2005 kit. It is a year old but seems to work pretty well yet. Is it possible that my test chemicals are just old?

Service posted this 12 September 2016

Hi Ras5114,

Thanks for the update! In my opinion your CYA is too high as your CYA gets higher it starts to render your chlorine ineffective, here is a useful chart showing the relationship between your CYA and Free Chlorine.

http://www.troublefreepool.com/content/128-chlorine-cya-chart-slam-shock

The bad thing about lowering CYA is that it can only be done by draining your pool and re-filling with fresh water. If you do decide to drain your pool and refill with fresh water then I would hold off on shocking until you drain, re-fill and re-test your CYA. If your pool is a non-salt water pool then the ideal range for your CYA is between 30-40 PPM.

Thank You

Patrick

Thank You

Patrick

www.inyopools.com

ras5114 posted this 12 September 2016

Well that isn't what I wanted to hear. I'll start working on a partial drain and refill.

How does the CYA get too high. It was about perfect last year. We have had a lot of rain this year. Would that affect the CYA levels?

Service posted this 12 September 2016

Your CYA can get high from Chlorine Tablets as chlorine tablets are called Stabilized Chlorine meaning that the tablets release a small amount of CYA into the pool, over a long period of time (i.e. a pool season), your CYA will gradually increase from the slow release of CYA from the chlorine tablets. One of the benefits of using liquid chlorine is that it does not have CYA in it so the liquid chlorine will not increase your CYA. 

Thank You

Patrick

www.inyopools.com

ras5114 posted this 12 September 2016

Patrick,

Tell me what you think about this idea. Sounds like the high CYA levels could be having some effect on my chlorine readings. The only way to get that down is to partially drain and refill the pool. Given the fact that the water is very clear and no sign of alge, and I'm getting ready to drain the pool past the return for winter anyway, what do you think about hitting it with one of your closing kits, draining it down and covering it for the winter. Then work at CYA, chlorine and PH levels in the spring.

Seems like an awful wast of time (and water costs) to drain, fill and drain again.

InyoAlan posted this 12 September 2016

Hello Ras5114,

I am sure that Patrick would agree that the partial drain and winter closing kit would be a great choice. Just remember that when you open the pool and have added fresh water, check the CYA levels at that time. You may need to do an additional partial drain and refill if your CYA level is not in the recommend 30-40ppm range.

Thank you,

Alan

ras5114 posted this 13 September 2016

Thanks guys! That's the answer I was hoping to hear. Two more quick questions for you then I'll leave you alone.

I have a looplock mesh winter cover. Even though I drain the pool below the returns, by spring the snow melt has filled the pool to the top. Does snow melt (and rain for that matter) contribute to the high CYA levels? Normally I just work to clear the water in the spring without draining it down. With the problems I've having, next spring I will drain it down and refill.

Secondly, with my chlorine and CYA issues, is there a particular closing kit you carry that you would recommend?

InyoAlan posted this 13 September 2016

The snow melt and rain water will only contribute to dilute and lower the CYA levels, as fresh water is the only real way to reduce the CYA levels.

As far as a winterizing kit, I would steer clear of the DI-chlor chlorine kits as Di-chlor will only increase your CYA levels. I would recommend the 15,000 Gal. Winterizing Kit W/ Chlor-Free Shock. If you want to add chlorine in some form, I would recommend purchasing Super Zappit (73% Cal. Hypo.) for shocking. This product will not increase your CYA levels. You can also use Liquid Chlorine if you would like.

Have a great winter!!!

Alan

ras5114 posted this 13 September 2016

Thanks again for all your help!!

InyoAlan posted this 13 September 2016

You are welcome!! Thank you for choosing Inyopools.com for all of your pool care needs!!

Alan

Close