Can't keep chlorine in pool (all chemicals balanced)

Jun 26, 2016
14
Phoenix AZ
Hi everyone, I have an 11k gallon in-ground pebbletech pool. Live in Phoenix, AZ.

I can't keep chlorine in my pool the last couple of months, even during the recent cooler weeks (90 degree days). All chemicals are balanced and I keep chlorine tabs filled in a floater at all times. I am having to add shock at least once a week and in a couple of days it's gone, even with the tabs in the floater filled (using In The Swim tabs). Something is eating my chlorine and since it's not too hot lately it must be algae? Even though there is no sign of it at all.

Every Friday I add Super Algecide, Super Blue, and Pool Perfect +PhosFree. I also scrub all walls and steps. There is no sign of algae, water is super clear and everything generally looks nice.

Full disclosure, I ran low on chlorine one week during the summer and my phosphates skyrocketed but very minimal algae was seen. I had to add a bunch of Phos Free and shock. I also cleaned the filters multiple times. Since then though my phosphates are at proper levels.

The only thing that is high are my total disolved solids. Could this be what is eating up my chlorine? I drain and refill every two years and am due to do it this next season. Should I just do it now?

See below for my readings:
* Cyanuric acid - 80ppm
* Total Alcalinity - 100ppm
* pH - 7.2
* Copper - 0
* Iron - 0
* Phosphates - 100 (was all the way up to 1500 when I ran out on chlorine. Added Phos Free and shock to get levels back down)
* Total Disolved Solids - I don't have the reading in front of me but it was quite high. This is the only thing that is off besides the chlorine of course.

Any help would be greatly appreciated. I am leaning toward just draining and refilling, however I'd like to get through the winter with the pool as is and do the drain/refill next season if possible.

One last thought, my cartridge filters are about 3 1/2 years old (4 of them in a Pentair unit). How often should they be changed generally? I wash them multiple times a year and they clean up nicely.

Thanks!
 
I am sure an expert will chime in soon, but in the meantime try perusing through pool school. Particularly the abc's of water chemistry.

We do not trust pool store results, which it looks like you have posted. We do our own testing, preferably with the TF-100 kit but the K-2006C is acceptable too. Test kits compared

As far as the TDS, that is not something we test for or react to so far as I have seen. Phosphates have little meaning either if you maintain your FC to the proper level for your CYA. See also CYA/Chlorine chart. CYA / Chlorine chart

Much of what you have been adding are probably working against you and costing you money, I will let the experts give you details but highly advise purchasing one of the kits ASAP. It will save you big $ quickly and the tests are fairly easy too.

Also, please add your pool information to your signature, it will help them help you.
Settings then signature. See my signature on format. If you are on smart phone, turn sideways to see signature.

Good Luck!
 
You,

The chemicals you are using are not what we recommend. Looks to me you are following pool store recommendations and using their "free test" services. We promote and support a methodology that enables pool owners to test their water themselves using a test kit that's been proven accurate and then using this information to calculate your pool treating needs. The chemicals used are almost all generic, readily available from big box stores are are dirt cheap. Most pools your size can be treated at about ~$10/mo with spectacular results. Oh, and another important fact: we don't sell anything. So our advice is never conflicted. If this sounds appealing to you please read Pool School and ABC's of Pool Chemistry. I have also added a few links to important videos below. In order to use this system you will require a test kit. We recommend two and they are described in Pool School. You will need this to get started so please order asap.

I hope you decided to join in with the thousands of TFP'ers like me that have used this methodology for years and always had perfect pools to rave about. And if so please ask any questions you may have. Pool care can be intimidating but it shouldn't be. You don't need to be a chemist or an expert. We have many of those here to support you but you don't need to be one to do this yourself.

Good luck and I hope this is helpful to you

Chris





 
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You did not mention your current free chlorine level or what your target FC is. Most folks are not aware of the chlorine/cya relationship and follow the industry standard of 2-3 PPM...considerably higher chlorine levels are required if you CYA is at 80.
 
YouLoze, first off let me welcome you to TFP :) We are an international forum of pool owners who have learned that the best way to maintain our pool's chemistry is to take control of the testing and chemical additions ourselves. The TFP methods have been found to be better for pool equipment, swimming satisfaction and least costly compared to what pool stores want to tell you and sell you.

Now, taking your post apart..... I'll interject some comments-
"I can't keep chlorine in my pool the last couple of months, even during the recent cooler weeks (90 degree days). All chemicals are balanced and I keep chlorine tabs filled in a floater at all times. I am having to add shock at least once a week and in a couple of days it's gone, even with the tabs in the floater filled (using In The Swim tabs). Something is eating my chlorine and since it's not too hot lately it must be algae? Even though there is no sign of it at all.
Balanced per pool store is not the same as balanced to us here at TFP. Each time you had pucks and "shock" (is that a granular product?) you most likely are raising your stabilizer level along with any chlorine it gives you. Almost equal parts! The more stabilizer (CYA) you have in the water, the higher your chlorine requirements are....and if you're listening to pool stores they'll sell you more! It turns into quite a vicious circle. You can have algae hidden in nooks and crannies, such as behind lights, under stairs, etc. Algae can look like slightly cloudy water yet never look green also.

Every Friday I add Super Algecide, Super Blue, and Pool Perfect +PhosFree. I also scrub all walls and steps. There is no sign of algae, water is super clear and everything generally looks nice.

Wow! That's gotta be a pretty penny! Algaecide, especially copper containing algaecides work best in helping avoid algae but not so good at treating algae present, nor does it sanitize the water. Copper alone builds up and can cause some nasty stains to your pool surface.
I have no clue what Pool Perfect is, but I know PhosFree is an expensive dilute version of a phosphate eliminator that some choose to use, but we can advise a much better version than "PhosFree".


Full disclosure, I ran low on chlorine one week during the summer and my phosphates skyrocketed but very minimal algae was seen. I had to add a bunch of Phos Free and shock. I also cleaned the filters multiple times. Since then though my phosphates are at proper levels.

If your chlorine is too low its an invitation to algae. Phosphates are algae food and since we teach that they matter little to most since we keep our free chlorine at such a consistent level there is no algae, so having its food available doesn't effect our pools. We have posters here whose phosphate levels are in the thousands yet they never have problems.

The only thing that is high are my total disolved solids. Could this be what is eating up my chlorine?
Total Dissolved Solids are the recipe for the *everything* in your water. That includes calcium, salts, chlorine, etc. They mean nothing to us.

I drain and refill every two years and am due to do it this next season. Should I just do it now?

See below for my readings:
* Cyanuric acid - 80ppm
* Total Alcalinity - 100ppm
* pH - 7.2
* Copper - 0
* Iron - 0
* Phosphates - 100 (was all the way up to 1500 when I ran out on chlorine. Added Phos Free and shock to get levels back down)
* Total Disolved Solids - I don't have the reading in front of me but it was quite high. This is the only thing that is off besides the chlorine of course.

I don't see any Free Chlorine (FC) or Combined Chloramines (CC) readings above. The FC is the good stuff, the CCs are the "cooties" or contaminates that the chlorine is working to overcome. Ideally you want Zero CCs, or a very minute amount. Your CYA is high (assuming we can believe its accuracy, which is doubtful) for a non-salt water generated pool. For Arizona sun we would prefer to see it around 50ppm. Most folks would be in the 30-40 range, but high sun areas sometimes need more than most.

Any help would be greatly appreciated. I am leaning toward just draining and refilling, however I'd like to get through the winter with the pool as is and do the drain/refill next season if possible.

One last thought, my cartridge filters are about 3 1/2 years old (4 of them in a Pentair unit). How often should they be changed generally? I wash them multiple times a year and they clean up nicely."
We recommend you clean your filter when the filter pressure rises by 25% over clean pressure.

We advise folks to obtain a GOOD test kit and learn what's actually in their water and don't put any chemical in the pool that it really doesn't need and that you don't know what the response will be. Test Kits Compared

Some quick reads--> ABCs of Pool Water Chemistry

Holler back with any questions.... we like helping folks :)

Maddie :flower:

 
Thank you all for your replies! I didn't receive an email notification that there were replies to this thread, so I just saw them. I will read through them and reply as needed.

In the short term I will update my profile. Also, I do use my own test kit (All clear 5 way test kit) but it only tests Chlorine, pH, Alcalinity, etc. I will order the advised kit asap. The only time I go to the pool store is to test phosphates and the like.

Will reply with more info after reading through replies. Thanks!
 
Based on my crash reading and a couple of the replies it seems like getting my CYA down will help me retain the chlorine better. It looks like a product called Bio-Active is recommended in one of the TFP articles I read?

I am ordering the TF-100 kit tomorrow, and I'd like to order anything else I will need in the short term, at the same time. Does anyone here recommend Bio-Active to reduce the CYA or should I just drain and refill at this point since I plan to in the spring anyway?

Also, to answer the questions about my free chlorine level. I didn't put that in the original post because it was literally zero when I checked it yesterday. As mentioned, I am having a heck of a time keeping it in the pool, but it seems that the high CYA levels due to the chlorine tablets is what is causing it.

Thanks again for all of the help!
 
We were all sorry to find that the Bio Active is a waste of money and time.... worked minimally like one time out of 10? Far too finicky to test for that kind of money with such a poor track record here, IMO.

Good choice for the TF-100. That's a better buy than the comparable K-2006C which costs a mess more. When you kit comes in tell us:
FC
CC
pH
TA
CH
CYA

Then we'll know more what to tell you. 'k?

Maddie :flower:
 
You have to turn on email notifications.. that isn't on by default...

If you haven't ordered yet, you might consider getting the bundle that includes the stirrer. it comes in handy. It sounds like a SLAM may be in your future to get things set right.. so you might also consider the XL option as you get more reagents.
 
worked minimally like one time out of 10?
I don't remember it working at all. There was some reports of success but they were pretty sketchy and those posters I don't think have ever posted back. In short, it's a bogus product.

Please read "The "ABC's of Pool Water Chemistry" up in Pool School
 

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We were all sorry to find that the Bio Active is a waste of money and time.... worked minimally like one time out of 10? Far too finicky to test for that kind of money with such a poor track record here, IMO.

Good choice for the TF-100. That's a better buy than the comparable K-2006C which costs a mess more. When you kit comes in tell us:
FC
CC
pH
TA
CH
CYA

Then we'll know more what to tell you. 'k?

Maddie :flower:

Thanks again for the replies everyone!

Too bad to hear about the product not working, but I'm glad I didn't order it. The only reason I considered it was because it was mentioned in one of the TFP articles I read.

I am ordering the TF-100 kit now (will try to find the one with the stirrer per mguzzy's suggestion). I will post readings once I have the kit.

Thanks!
Mike
 
TF-100 kit ordered, but unfortunately it is not eligible for Prime on Amazon and I couldn't find it anywhere else that would ship it faster than ground. Won't receive it until next week so I will update then.

Until then I will do my best to keep the chlorine content up.
 
If you order the TF-100 and Speedstir thru TF Testkits (order total > $100), you will get free shipping. And if they ship it USPS Priority Mail you should have it in about 3 business days. And you can't beat their customer service either.

Amazon isn't always the best choice. But if you do use Amazon, consider using Amazon Smile and choosing TFP as your designated charity.
 
Did you look at tftestkits.net? I find the price there is competitive with amazon and it ships very quickly.

Thanks, I did check there but with shipping it was more than Amazon and still ground.
I just went ahead and ordered from Amazon...believe me I am not a huge Amazon advocate but the price was cheaper and shipping was the same time frame so I went with the place I've done business with in the past.

Hopefully I get it sooner than projected, which has happened in the past with simar situations.
 
You can get the SpeedStir on Amazon as well. Although it is considered optional here, I dont think I could live without mine. It makes the testing more accurate, faster, and more fun.

My wife actually calls me Beaker from the muppets when she seems me testing. I cant believe she has not gotten me a T shirt yet.
 
Ok, much to my delight my kit arrived earlier than anticipated. I just took my readings.

Based on the extremely high CYA and Calcium Hardness levels I'm assuming a drain/refill is in order. Keep in mind I live in Phoenix and our water here is extremely high in calcium. I drain every two years and this is my second year, so it's about time anyway.

FC - 1.5
CC - maybe .5
pH - between 6.8 and 7.0 (interesting because it generally registers in the 7.2-7.6 range during the season and sometimes I actually need to lower a bit)
TA - 120
CH - I lost count after so long lol. Somewhere between 55 and 60 drops which equates to over 1,400!
CYA - Also extremely high. It didn't even get to the "100" mark before the black dots disappeared. It's probably about 1/2" under the 100 mark.

Thank you for the help everyone! What are your thoughts?
 
You,

You can use the dilution method to estimate how much water needs replacing and you can use the exchange method described in numerous posts here including this one. I've never had to exchange and deal with your AZ/NV water composition issues but we have an expert that advises on this all the time. I'll see if I can raise him. @mknauss

Chris
 
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With that data a full drain/exchange is needed. This time of year you can drain using a high power sump pump and refill.

I would suggest getting a SWCG and ditching the pucks. Your pool will be far more pleasant to swim in.
 

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