can't keep chlorine level; phosphates?

[JasonLion]

Welcome to TFP!

Phosphates really don't matter at all. Mostly they are a way for pool stores to scare you into buying expensive chemicals.

With a vinyl liner there isn't any need for calcium.

Your TA is quite low. You should raise it some, especially if you are using trichlor tablets for chlorine. Of course, if you are using trichlor it is time to stop using it, because that is where your high CYA level is coming from.

Your CYA level is very high, which is probably why you can't maintain your chlorine level. When CYA is very high you need to add extremely large amounts of chlorine all at once to make any progress against algae. By far the best thing to do is to replace some water to get the CYA level down to a more reasonable level.

 

[JohnT]

Welcome to TFP!

How do you chlorinate the pool normally?

You really need to add some liquid shock or unscented laundry bleach to get some chlorine in there. With your high CYA level, you need to shoot for a FC reading of 12ppm.

Don't worry about the calcium, it's not important in a vinyl pool. Your TA is also probably okay, but don't buy the stuff from them to raise it. They sell overpriced baking soda, and you can buy it much more cheaply at a warehouse store.

The key piece you are missing is knowing the state of your water. Pool store testing tends to be unreliable. Get your own test kit, and you'll save more money in the first year than it costs you. The Taylor K-2006 is a good one, and the TF-100 at tftestkits.net is also a good one.

Read the articles in Pool School pool-school/ to get a handle on things.

John

 

[duraleigh]

Renee,

Welcome to the forum.

Chlorine in your pool is a consumable item......it will always be consumed by two things.....the Sun and organics (algae) in your pool.

You have protection from the sun with the Cyanuric Acid. Therefore, it is almost a sure bet that you have organics (algae) in your pool that is consuming the chlorine.

How have you been adding chlorine? How often? How does your water look?

 

[frustratedpoolmom]

I am a new member, and have read a lot of previous posts to try to answer my questions, but am having trouble taking it all in and figuring out what to do next. I would appreciate any help you guys can give us.
Renee

I understand, I have been there. Been pool stored many a time myself in the old days... :grrrr:

You're been given great advice - I know you are feeling a bit overwhelmed right now and it's alot to try and take in all at once. :blah:

So to just emphasize a few points:

1. You need your own test kit, so you aren't subjected to bad pool store advice and subjected to buy expensive chems your pool doesn't need.

2. While you wait for your test kit to arrive, start draing your pool, 1/3 down at a time is safe enough, refill, recirculate, retest the CYA and repeat a partial drain if necessary. Try to get the CYA down to 70 at the very least.

3. Once your CYA level is down, you can begin to "balance" the pool water. You'll start by checking the PH/TA and if those are acceptable, you will then shock your pool with bleach/liquid chlorine.

You need to read How to Shock Your Pool, and learn how to use the Pool Calculator.

Hope this helps, ask questions here if you are still uncertain on what to do.

 

[duraleigh]

1. Pool stores are horrible at testing for CYA.

2. No, you have no chlorine because it is being consumed by algae (invisible)

3. The tablets are causing your CYA to be too high....making the chlorine much less effective.

4. Yes, you should switch to bleach.

5. If your pool is vinyl, you have no need for calcium.

6.

Is that just what they tell people now to get them to buy more chemicals?

Yes and No. In fairness, it's often a lack of knowledge.

There's lots of articles up in Pool School that will help you sort this out. Ask lot's of questions....there's plenty of good folks here who will offer a lot of assistance.

 

[frustratedpoolmom]

See my response in Bold.

Just wondering how come they are telling me my CYA is well within the normal range? Could it just be a testing range difference? Or is that pretty standard? And a high CYA is why we have low chlorine?
According to our Special Contributor, Waterbear, Chemtura, the maker of the ALEX testing system, says that up to 200 PPM of CYA is acceptable. ( It's not.) Whats interesting, is Chemtura is the parent company of Aquachem, which markets trichlor products (and test strips). Other Chemtura companies in the US include Pooltime, Guardex, Sun, Bioguard, Simplicity, Omni, and Hydrotech. They have a bit of a "conflict" KWIM?

If you look at the CYA chart - you can see that the higher the CYA level, the higher the required FC. At high levels, it simply isn't practical to try and maintain the FC with that much bleach. The tablets don't produce enough FC to be effective, so "nascent" (or invisible) algae takes hold - consuming the chlorine as it is added. Once the CYA is lower, you can shock the pool, kill the algae, and then FC levels should be stable. We recommend just using bleach because it doesn't increase CYA and it doesn't lower PH/TA (all three are side effects of trichlor tablet use).

Also, could the low calcium affect any other parts of the plumbing/filter/fixtures? If not, then I'm seriously pretty angry that I have put almost $80 worth of calcium in my pool for nothing.
No, pool store myth. I'm right there with you, having been sold that same bill 2 years ago. I only was out about $40, but I was still pretty upset at the time.

We use chlorine tablets in the filter. Should we switch to bleach?
Yes. Do you mean skimmer? Tablets should never be placed in the skimmer unless the pump runs 24/7. The tablets are acidic, and overtime can cause the skimmer parts to become brittle and break, and can cause damage to the pump equipment if they sit in the skimmer with the pump off.

The pool store told us that the reason we can't keep a good chlorine reading is phosphates. Is that just what they tell people now to get them to buy more chemicals?
Sort of....Phosphates ARE algae food. BUT....in a properly chlorinated pool, phosphates are irrelevant. Our forum admin, Jasonlion, has a VERY HIGH phosphate level and never gets algae, because he never lets his FC drop below the "min" level. You don't need phosphate removers, they are just profit-makers for pool stores.

By the way, the most confusing thing is that the pool looks wonderful. I don't see or feel anything funny or off. Could I still have algae eating up the chlorine?
Yes.

My husband just picked up 12 pounds of baking soda at Sam's for $3.99. Thanks for that tip!!!!

I will keep reading in order to understand more on my own, but in the meantime, thank you for helping us figure out what to do with our pool.

Renee

Glad we can help, it's sort of "paying it forward" many of us having been pool stored in the past.

 

[reebok]

Re: Need help

you're going to have to find out what the cya level is for sure. I wouldn't order test strips, but I would order a kit from http://www.tftestkits.net it should come in 2-3 days and it's going to be the #1 thing that helps you with your pool.
you really need to read pool-school/ specifically the water chemistry section. ignore all recommendations from the pool store.
you aren't going to know what to do until you get a full correct set of test results. how does the water look?

 

[duraleigh]

Re: Need help

You guys are teaching us a lot about how to balance our pool water,

Renee,

Being blunt, the first lesson is to stay out of that pool store for testing and advice.

1. Phosphates are irrelevant in your pool.

2. 30-100 is not an acceptable range for CYA

3. Test strips are just as bad as the pool store testing....often worse.

4. It is very, very difficult to apply the BBB principles we teach without doing your own drops-based (accurate) testing

Again, I don't mean to be abrupt but I am being very honest. Read almost any pool water thread on this forum and you will hear others talk about pool store testing and test strips.

 

[Butterfly]

Hi Renee and welcome to the forum

It would be helpful if you added your pool and equipment specs to your signature.
Go to User Control Panel (top left below TFP logo), select Profile, then Edit Sig.

The best investment we made in our pool was a good test kit.
There is an article in Pool School on comparing test kits.
The best bang for the $ is the TF100 sold by duraleigh at http://www.tftestkits.net .
It is the kit of choice around here. This is what will put you in control of your pool.

Test strips are notoriously inaccurate and are not recommended.

 

[frustratedpoolmom]

See my response in bold.

Okay, now I'm ready to just close the darn pool for the season. I don't know what else to do, and I'm getting frustrated. (Can you tell?)

I didn't get my screenname by accident....if you close now, you'll have the same problem, if not worse, come spring.

Anyway, we don't have the test kit yet,
Does this mean one is on order? If not, at the very least, go to Wal-mart and look for the HTH 6-way test kit. It accurately tests PH/TA and has an OTO chlorine test. IT has enough reagent for 2-3 CYA tests. We need you to confirm, accurately, what your CYA level is. If it's over 70 you need to drain and replace some of your water, or you will very simply, fight a losing battle.

and in the meantime I figured I would just run to the pool store and see what they said I had for a chlorine level. The free chlorine is .1 ppm. So just to make sure I didn't start growing algae, we decided to shock the pool, figured it couldn't hurt, and just might help. We poured 5 gallons of liquid chlorine into the pool last night, let the filter run for 6 hours, and I just tested the water this morning. Even though they are test strips, and may not be the most accurate, we used them for years and I know they would at least register some chlorine if it was there. Well the free chlorine reading is showing nothing, although the total chlorine pad shows an almost normal range for the first time in weeks.

Free Chlorine is what you want. Total Chlorine being higher, means you have CC, which is what you don't want. CCs over .5 means you need to keep shocking the pool, running the filter 24/7. However, you aren't actually "shocking" the pool, you are teasing it....

Was the 5 gallons 12.5%? 5 gallons of 12.5% in your pool, would only raise the FC to about 20. If your CYA really is 125, then your actual shock level is about 47. (http://www.troublefreepool.com/chlorine-cya-chart-t2346.html)
This means you need twice as much chlorine as you think you did.

Here's a scenario to picture. You add 10 gallons of 12.5%. You wait an hour, retest, FC is back down to 5. You go to the pool calculator, enter in a FC of 5 and a shock level of 47, hit calculate, it tells you how many more gallons you'll need to reach 47 again. You'll repeat this process hourly at first, until the FC starts to hold for longer and longer periods, perhaps reaching a point where you only need to add chlorine morning and night. But at first, when shocking, you need to test hourly, and add bleach hourly.

So you can see, the process of shocking, is not dumping in "x" gallons, walking away and testing the next day. This won't accomplish anything. You can also see, that if your CYA is really that high, you'll be going thru ridiculous amounts of chlorine to try and defeat the beast. You need to lower the CYA level if it's really 125.

I really don't know what to think or do at this point, and although my kids love the pool, we have already invested so much in electricity, time, and money for chemicals this season. It is getting ridiculous at this point. Can anyone hazard a guess as to why this is happening, even not knowing for sure because I don't have my test kit? Even guesses would be greatly appreciated!

It's happening because (if the reading is accurate) your CYA level got too high, the FC is no longer effective, you have "nascent" algae that is consuming the chlorine as you add it, so when you test, it shows up as low or zero.
Thanks!
As far as how the water looks, it is crystal clear and looks and feels beautiful. (which only makes everything even more confusing)
If you stopped chlorinating, the pool would turn green within 1-2 days.

Here is the latest from analysis from the pool store (this is from yesterday, before we shocked it)

Free chlorine: .1 ppm Range: 1.0-3.0
Total Chlorine: .1ppm Range: 1.0-3.0
Combined Chlorine: .1 ppm Range .1-10.0
pH: 7.7 Range: 7.2-7.9
Hardness: 200 Range: 200-400
Alkalinity: 100 Range: 100-150
Cyanuric Acid: 125 Range: 30-150

Ignore their "ranges" they are outdated standard industry jargon that is not helpful, the 1-3 ppm FC is based on indoor pools with no CYA. CYA level dictates appropriate FC level.

Pool store testing will not help you. You can't rely on it, unforunately it's just not accurate and sometimes it's outright misleading.

Pool stats:
Inground: 33,000 gal. vinyl liner
Cartridge filer, Pentair chlorinator

IF you still have tablets in the chlorinator, take them out.

 

[sbluhm]

Quote:
Can anyone hazard a guess as to why this is happening, even not knowing for sure because I don't have my test kit? Even guesses would be greatly appreciated!
--snip--

This is happening because your CYA level is too high, despite what the pool store says. The higher the CYA, the more chlorine you need in the pool. This makes it harder to fight algae and even maintain a daily level of chlorine. Unfortunately, the only way to reduce CYA is partial water drains. You really could replace up to 50% of your water to get your CYA down to a manageable level. For some pools, partial drains are difficult (ex. mine has no bottom drain). Please start to do a series of partial drains in order to get your CYA down. When you do, you will be much happier with your ability to manage the chlorine level.

You also need to understand why the CYA got so high... most powdered chlorine (including the pucks you've been using) add CYA to the water, so it's important to only use them only if you are aware of your CYA level and want to increase it. For most of us, that is fairly seldom and so we use the liquid bleach on a daily basis to keep chlorine in the pool.

A lot of us have been in the exact position you are... tired of spending $50 - $100 (or more) every time you walk in the pool store, not understanding why the chemicals are acting the way they are, etc.. Please do yourself a huge favor... order a good test kit, and read Pool School on this site. You will be much happier with your pool, how much you spend on chemicals, and your ability to understand and maintain it.

Good luck!

 

[anonapersona]

We poured 5 gallons of liquid chlorine into the pool last night, let the filter run for 6 hours, and I just tested the water this morning. Even though they are test strips, and may not be the most accurate, we used them for years and I know they would at least register some chlorine if it was there. Well the free chlorine reading is showing nothing, although the total chlorine pad shows an almost normal range for the first time in weeks.

The Chlorine was used up by organics and produced Combined Chlorines. So, Free Chlorine = 0, Combined Chlorine = "almost normal number", and Total Chlorine (which is Free Chlorine plus Combined Chlorine) = "almost normal number"

The fact that your pool is clear is great. My pool was clear too, before I got it under control. It just had this slight green film here and there some days that I had to scrub, usually after we used the hot tub. I was running it with very low chlorine, and rather high CYA. You won't know how low or how high until you get a dependable test kit. Your pool stores are probably using the same strips that you are buying so that getting strips won't get you any more info than you have from the various stores, all conflicting.

 

[reebok]

1. I don't remember that thread in particular, but I can tell you that the methods outlined here will always work, whereas different methods and pool store methods may or may not work, and they may make the problem worse. a low fc problem is basically an algae problem, whether you can see it yet or not. removing phosphates may work for you, and you are certainly welcome to try any method you would like. but that stuff is expensive and it may not work since phosphates are not the only algae food, just the only algae food that the companies have figured out how to make an expensive chemical for to get rid of it. this product also has a bad habit of making pools really cloudy. if you want to follow the method here, which I certainly recommend after 3.1 years of algae, you need to start draining. my cya is at 70, and it works fine for me, I just have to keep a bit higher fc than others with the recommended cya of 30-50 (assuming no swg). this would be an approx 42% drain to get down to 70ppm. but like I say, that is above the recommended levels, so do what you want.

2. depends on your comfort level and water table. there is a reason this article pool-school/read_before_you_post mentions how to add your location to your profile. this is one of them.

3. absolutely stop the trichlor. this would be like shooting yourself in the foot or cutting off your nose to spite your face. I think the recommendation is two small (96oz) bleach jugs per night. you can work out that amount for whatever product and packaging you are using.

4. it will. you should be shooting for about 12. there is an article in pool school that details how to use the calculator.

it makes a lot more sense when you actually start doing it and seeing the test results.

 

[frustratedpoolmom]

1. No. You need chlorine, but first you need to drain 40-50% of your water and replace it with fresh.
2. It depends (as Reebok said) on your water table and type of pool. I would say go down about 1/3 (which is safe for most pools), refill, recirculate for a few hours, and then repeat 1/3 down, refill, recirculate for a few hours. Retest your CYA after the second drain/refill/recirculate, I think you'll be in a more acceptable range. At that point, retest CYA, PH and TA. Adjust PH/TA first, if necessary, then begin to shock. Follow the instructions in How to Shock your Pool.
3. You test each night, you take the test result and that is your "now" value for the pool calc. Your "target" is from the CYA chlorine chart (or the pool calc itself will give you a recommendation if you enter in all the information correctly). You enter the values, hit calculate, and it tells you how much bleach that is. The idea is to stay above your "min" level, and the target addition should be enough bleach to keep you above the min.
4. There is an article in Pool School that teaches you how to use the Pool Calculator. You will need to be able to use the calc to adjust PH/TA and determine how much bleach to add for shocking and daily chlorination.
5. It's risky, with the chlorine so low, I'll be honest. Once you have adequate chlorine levels, provided your water is clear, it's okay and safe to swim all the way up to "shock" level for your CYA. Many users swim at higher than shock, it's a 'to each his own' kind of comfort level thing.

 

[frustratedpoolmom]

Hang in there. Don't forget some POP (Pool Owner Patience)

 

[duraleigh]

Report your current CYA level and that'll get us started helping you.

 

[frustratedpoolmom]

You were on the verge of green all along, the chlorine you had been adding was just keeping it at bay. Once you get the CYA into range and start the shock process, it will clear up quickly with frequent chlorine additions.

You can add some chlorine now if you like, but you'll just be draining it out with the water during the second drain/refill. It's up to you, if it were me I'd just go ahead and drain/refill/recirculate and retest CYA.

 

[reebok]

you should do it again, yes. the way I see the issue is, some of the bleach you add now will simply be lost on the ground due to the drain. on the other hand, you risk getting algae, if you don't already have it, by not adding bleach. if you do, you'll have to shock with quite a bit of bleach. I vote to add it now based on an ounce of prevention is worth a pound of cure, but you'll have to make your own decision.

 

[frustratedpoolmom]

I vote drain first.

To reach shock level you would need 25 small jugs of bleach. And that's only teasing it, then you'd just be draining 1/3 of it out....I don't see the point.

Drain down 1/3 one more time and you should be golden. Then you can shock at a much lower level and use much less bleach.

 

[frustratedpoolmom]

Yeah, you are getting this!

So you test hourly, and add enough bleach to hold 20. You do this until the 20 holds overnight and you lose less than 1ppm and your CC is .5. Since you aren't testing with an FAS-DPD chlornine test, you need to hold shock level until the water is cleary and "sparkly". Once you see "Sparkly" nothing else will do. Once these criteria are met, you will let the FC drop down to your "normal" level.

Once you are done shocking:

Each night, you'll test the chlorine. You'll want to stay above 4 at all times. So say you test and the result is 4. You will calculate enough bleach to add to reach 6 or 7, which is your goal or "target" for the pool calc. "4" would be your "now". Enter these values in and hit calculate and it should tell you how much bleach it is to raise the FC level by 2-3 ppm. This is the average loss in normal pools. Some days you may lose less, some more. Kinda depends on a number of factors.

So each night you'll test, enter the "now" result and the target of 6 or 7 and add that amount of bleach. This routine should keep you above the "min" of 4 and prevent another occurence of algae.

If you are having a pool party, make sure the FC is at 7 or 8 before folks swim. This will prevent the FC from dropping too low.

Okay, so get busy. If you're diligent your pool should be sparkly by Monday.

Holler if you need clarification on anything