I have an auto chlorinator and this summer I have been having algae problems. The pucks don't seem to be dissolving as fast as they used to and when I check the chlorine levels it is always lower than I would like. I have also been adding liquid chlorine periodically to try and boost the levels, but the auto chlorinator doesn't seem to be able to keep up. What could be going on? What can I check?
Auto chlorinator not working?
- Thread starter bwoodworth
- Start date
Hello. Do you have a test kit? If so, please let us know which one. Please also post your test results here, including FC, CC, CYA, pH, and TA. The first step is probably to get your pool balanced without the auto chlorinator.
I have this: Amazon.com : HTH 1273 6-Way Test Kit Swimming Pools Chemical Tester : Garden & Outdoor
Just tested:
pH: 7.2
Total Alkalinity : 90ppm
Free Chlorine: < .5
Total Hardness: ~300ppm
CYA: I tried to test, but the solution never got cloudy
Just tested:
pH: 7.2
Total Alkalinity : 90ppm
Free Chlorine: < .5
Total Hardness: ~300ppm
CYA: I tried to test, but the solution never got cloudy
You're off to a good start. Your CYA is probably zero. It's also known as stabilizer, and it's something you have to add manually. Without CYA the sun will burn off your chlorine very quickly. You mentioned you are having algae problems, so this is also probably responsible for a lot (maybe most) of your FC loss.
You'll need to test your combined chlorine (CC) level to determine if there's something organic like algae which is causing problems. Unfortunately it doesn't look like your test kit includes it. Please consider getting a TF-100 test kit from tftestkits.net or a Taylor K-2006C. They're more expensive but they come with larger quantities of chemicals and they can test your CC levels.
While you're waiting for your test kit to arrive, please review the "ABC's of pool chemistry" in the Pool School link on this site. It's a quick read. Then you'll want to bring your CYA and chlorine up to recommended levels, and if you have algae you'll most likely want to go through the "SLAM process" (also described in the pool school).
Once your algae problem is cleared up and your chemicals are at the recommended levels, continue to test your FC. CC, and pH about once every day or so, and the other tests (TA, CH, CYA) around once a week. You may want to do some research on this site to see whether it's worth getting your auto-chlorinator up and running. You might be better off manually adding chlorine or investing in a SWG.
You'll need to test your combined chlorine (CC) level to determine if there's something organic like algae which is causing problems. Unfortunately it doesn't look like your test kit includes it. Please consider getting a TF-100 test kit from tftestkits.net or a Taylor K-2006C. They're more expensive but they come with larger quantities of chemicals and they can test your CC levels.
While you're waiting for your test kit to arrive, please review the "ABC's of pool chemistry" in the Pool School link on this site. It's a quick read. Then you'll want to bring your CYA and chlorine up to recommended levels, and if you have algae you'll most likely want to go through the "SLAM process" (also described in the pool school).
Once your algae problem is cleared up and your chemicals are at the recommended levels, continue to test your FC. CC, and pH about once every day or so, and the other tests (TA, CH, CYA) around once a week. You may want to do some research on this site to see whether it's worth getting your auto-chlorinator up and running. You might be better off manually adding chlorine or investing in a SWG.
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Eh... No you're not. You're either adding Muriatic Acid or Sodium Bisulfate. CYA isn't for pH adjustment and if you were using it for that your CYA would be much higher.
Doh. You are right. I went and got my water tested at the shop and here were the results.
Free Chlorine: 0.09 ppm
Total Chlorine: 0.09 ppm
Combined Chlorine: 0 ppm
pH: 7.1
Hardness: 214 ppm
Alkalinity: 95 ppm
CYA: 19 ppm
They had me add a couple pounds of chlorine shock to bring the chlorine level up.
I'm thinking there must be something wrong with my auto chlorinator since there was basically no chlorine in the pool.
Free Chlorine: 0.09 ppm
Total Chlorine: 0.09 ppm
Combined Chlorine: 0 ppm
pH: 7.1
Hardness: 214 ppm
Alkalinity: 95 ppm
CYA: 19 ppm
They had me add a couple pounds of chlorine shock to bring the chlorine level up.
I'm thinking there must be something wrong with my auto chlorinator since there was basically no chlorine in the pool.
PoolNewb2020
Well-known member
You have to buy a proper test kit. The recommended tests kits are Taylor K-2006C or TF-100. You will not get advice from the experts based on store test results or test strips.
As for your chlorinator and chlorine levels, what kind of pucks are you using and for how long? If they are trichlor, then chances are your CYA is much higher than 19ppm, which by the way cannot be measured to single digit accuracy using normal methods.
Chances are your chlorinator works just fine, but algae is consuming your free chlorine. Chlorine is lost only to two things, sunlight and algae. Performing an overnight chlorine loss test would tell you if you have an algae problem, but you need at the very least a FAS-DPD test for chlorine. But if it turns out you have algae, you would need a proper test kit anyways, so getting one now is the best first step.
Meanwhile, I would stock up on liquid chlorine and add 5ppm worth of chlorine daily until you get a test kit. Using Pool Math that is 96 oz of liquid chlorine.
As for your chlorinator and chlorine levels, what kind of pucks are you using and for how long? If they are trichlor, then chances are your CYA is much higher than 19ppm, which by the way cannot be measured to single digit accuracy using normal methods.
Chances are your chlorinator works just fine, but algae is consuming your free chlorine. Chlorine is lost only to two things, sunlight and algae. Performing an overnight chlorine loss test would tell you if you have an algae problem, but you need at the very least a FAS-DPD test for chlorine. But if it turns out you have algae, you would need a proper test kit anyways, so getting one now is the best first step.
Meanwhile, I would stock up on liquid chlorine and add 5ppm worth of chlorine daily until you get a test kit. Using Pool Math that is 96 oz of liquid chlorine.
If you plan to return to using pucks once you get the chlorinator figured out, I would not add CYA as the pucks have it in them, and it will rise with their use.
Is the chlorinator inline or off line? An inline will be directly plumbed in the system. An off line will have smaller tubing connecting it to the plumbing.
Either way, they work by directing flow from the pump into the device to dissolve the tablets and direct the chlorine to the return line. Inspect everywhere water flows in and out of chlorinator to make sure it hasn't gotten crusted up. If it is offline, the very small hoses can be subject to clogging with build up.
If it is clogged with white scale, you can clean it with water-diluted muriatic acid.
Is the chlorinator inline or off line? An inline will be directly plumbed in the system. An off line will have smaller tubing connecting it to the plumbing.
Either way, they work by directing flow from the pump into the device to dissolve the tablets and direct the chlorine to the return line. Inspect everywhere water flows in and out of chlorinator to make sure it hasn't gotten crusted up. If it is offline, the very small hoses can be subject to clogging with build up.
If it is clogged with white scale, you can clean it with water-diluted muriatic acid.
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Ignore my previous post, I don't know what happened there. This is what I meant to post:
People here don't have much faith in pool store tests. I can tell you from my experience that my pool was a whole new world once I got a proper testing kit. I don't know if there's something wrong with the chlorinator, but you should probably use liquid chlorine until you get a proper test kit. If your CYA is really low, you would have a very hard time keeping chlorine in the pool. You could also have invisible algae eating up the chlorine. Read Pool School on this site, it's extremely helpful.
Thanks for all the responses. Based on what everyone is saying there might not actually be anything wrong with the auto chlorinator. I think what was happening is the algae that is visibly in the pool is eating the small amount that gets put in the pool every day. Now that I have the levels up and the algae taken care of the auto chlorinator should be able to keep up.
Assuming that the algae is actually taken care of, yes. However, it is unlikely that a single addition of shock is going fully kill the algae. You should read the SLAM process in the pool school section.
- Jul 17, 2019
- 3,748
- Pool Size
- 13000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Pentair Intellichlor IC-40
Nix... what is that, ideally what are the ingredients? That sounds like pool store magic to me, which is highly discouraged on here as they can be costly, add more problems to your pool, and likely are not good at actually tackling the issue at hand.
I looked it up. It's an algaecide and phosphate remover. It lists these ingredients: Alkyl (50%C149 40%C129 10%C16) dimethyl benzyl ammonium chloride: 40%, Other Ingredients: 60%.