no chlorine

What is floc, clarifier, stabilizer, cyanuric acid,
algaecide, brightener, dichlor, sodium hypo,
sodium bisulfate, ....??
jemae
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no chlorine

Postby jemae » Thu 17 Apr, 2008 23:38

Hi, I read a lot in this forum regarding CYA as stabilizer. Every day i add about 240 grams of granular chlorine (65%) to the pool which i put in the socks and placed it in the skimmer.

Through the readings, you need CYA to maintain chlorine. Dosing is done at night and the next afternoon around 12, chlorine almost 0.

The problem is I live in Malaysia and pool chemical is very hard to get. Any other alternative besides Muriatic acid? Please help.

The other is raising total hardness. Called the pool shop here to get calcium chloride, no joy....They said put normal household salt, which is sodium chloride.

Despite all these problem, the pool water is crystal clear. Fighting invincible enemy???

Thanks


chem geek
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Postby chem geek » Fri 18 Apr, 2008 01:44

If you are registering no chlorine, that could mean several things. It could mean not enough Cyanuric Acid (CYA) so that the chlorine is breaking down from the UV in sunlight quickly. However, if you still do not measure chlorine even adding it and then measuring at night, then that is not the problem. If the chlorine level is too high and you are using a DPD chlorine test kit, then it will bleach out the kit if it is above 10 ppm Free Chlorine (FC) level. Another possibility is that you have nascent algae growth or have something else consuming chlorine such as leftover ammonia/urea.

I'm not clear if your granular chlorine is Dichlor (anhydrous, not dihydrate) or Cal-Hypo 65%. If it's Dichlor, then for every 10 ppm Free Chlorine (FC) you add you are also increasing the Cyanuric Acid (CYA) by 9 ppm. If it's Cal-Hypo, then for every 10 ppm FC you add you are increasing the Calcium Hardness (CH) by 7 ppm. Either way, you are probably building up too much of the extra ingredient (CYA or calcium).

You want SOME CYA in the water, but not too much as it reduces chlorine's effectiveness. Usually, around 30-50 ppm CYA is sufficient. After you reach your desired CYA level, you should switch to using an unstabilized source of chlorine such as chlorinating liquid or unscented bleach.

An alternative to Muriatic Acid is dry acid which is sodium bisulfate. However, Muriatic Acid, which is Hydrochloric acid, is better in that it does not increase sulfates.

The pool store is completely wrong saying to use regular salt. That would just increase chloride, but if you want to increase calcium hardness, then you want calcium chloride. If they don't have that, then you can get Cal-Hypo (calcium hypochlorite) as your source of chlorine as it will increase CH as I mentioned above.

You can learn a lot more by reading the Stickies here .

Richard
jemae
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Postby jemae » Sat 19 Apr, 2008 00:54

Thanks,
I've tried diluting the water to 5 and 10 parts and test. still, very low or no chlorine reading.

Hydrochloric acid i have, but not sure what is the dose. I am afraid to add it because the ph is stable at 7.2 and never change.

The other choice the pool shop gave is to use tablet chlorine which they said is 95% chlorine.

Thanks again
chem geek
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Postby chem geek » Sat 19 Apr, 2008 01:12

The tablet chlorine (Trichlor) will be much more acidic than what you are using now so would make the pH drop and you'd have to add pH Up to compensate. It's an option that would add CYA somewhat more slowly since for every 10 ppm Free Chlorine (FC) added by Trichlor, it also adds 6 ppm to CYA.

Can you look at the label of the 65% chlorine to see if it says something with "Dichlor" in it or if it says "Cal-Hypo" or calcium hypochlorite? I'm guessing that it's problably Dichlor (Sodium dichloro-s-triazinetrione) and that your Cyanuric Acid (CYA) level is very high as a result of using it. That makes your chlorine very ineffective. In other words, you've probably got too much stabilizer rather than not enough. Remember that for every 10 ppm Free Chlorine (FC) you've added with Dichlor, it also adds 9 ppm to CYA so it builds up very quickly.

Does your pool store sell chlorinating liquid? How large is your pool? I assume you can get bleach in the grocery store -- do they sell 6% bleach such as Clorox Regular?

As you've surmised, if your pH is stable and not high, you don't need Muriatic Acid.

Do you have a good test kit that can test for Free Chlorine (FC), Combined Chlorine (CC), pH, Total Alkalinity (TA), Calcium Hardness (CH) and Cyanuric Acid (CYA)? Can the pool store test for these? To figure out what you need to do you really need to know your current numbers.

Richard
Guest

Postby Guest » Sat 19 Apr, 2008 01:46

just ran to the store room and read the label

It is calcium hypochloride, active contituent 700 grams/ kg. granule

hydrochloric acid, minimum content 33%

Every night i add about 240 grams of chlorine ( 15000 gallons). Never actually add the acid since the ph is stable. should i add some acid?

from what i understand, you said every time i add chlorine, i will also increase the hardness. my pool has been running for about a month, that probably why the hardness is not increasing yet.

What actually is the correct dose for the acid and chlorine? I don't think i can find liquid chlorine here. The normal supermarket chloroc is very expensive here.

Thanks
Guest

Postby Guest » Sat 19 Apr, 2008 01:56

The test strip i use is the normal 5 in 1 strip which i bought in australia.
It test: Total hardness as ppm CaCo3
Total chlorine
Free chlorine(bromine)
Total alkalinity
Ph

I planned to get a better test kit end of this month when I go down under again.

And, the chlorine I use is hydrated, any different??

Thanks
chem geek
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Postby chem geek » Sat 19 Apr, 2008 12:59

Thanks for the info. That is very helpful. The 240 grams (8.5 ounces weight) of 65% Cal-Hypo will add 2.7 ppm chlorine to the pool as well as 1.9 ppm Calcium Hardness (CH). So after one month you've only increased the CH by around 60 ppm so not very much. Of course, we don't know what level of CH your pool water started with.

If the Cal-Hypo product says "Calcium Hypochlorite Dihydrate" as its ingredient, that's fine. Dichlor is also typically a dihydrate as well. The hydrated forms of chlorine are less flammable so have less strict transportation and storage requirements.

It is really important to get the full set of test measurements because if your pool's calcium level is really low, then this can be corrosive to plaster. Is your pool a plaster/gunite pool or is it vinyl or fiberglass? Also, what is the reading from your test strips of Total Hardness and Total Alkalinity since we can estimate Calcium Hardness from the Total Hardness.

When you get to Australia or even before then see if you can get a good test kit. Ideally, get the Taylor K-2006 which if you purchased online from the U.S. you can get a good deal here or you can get the TF100 test kit from tftestkits(dot)com here . On another forum, there's another person from Malaysia here and you can read more here about how the TF100 may be able to be sent to Malaysia so check with Dave at tftestkits(dot)com. Either that, or when you are in Australia get the Taylor K-2006 (it may be hard to get -- the K-2005 is more common and is OK, but not as good for the chlorine test).

When you started up your pool, did you add any Cyanuric Acid (CYA) to it? If not, and if your pool is exposed to sunlight, then that would explain why you aren't holding any chlorine. You need to either get pure CYA or you can get Dichlor if your pool store has this (Trichlor is OK, but will take longer). If you get CYA directly, then this is slow to dissolve so you'd need to put it in a sock or panty hose and hang it over a return flow which will take a couple of days. If you get Dichlor, then you can just use Dichlor as your source of chlorine for a while, knowing that for every 10 ppm FC you cumulatively add, you also get 9 ppm CYA. You should probably get your CYA up to 30 ppm and see what your chlorine usage becomes. You can easily add more CYA, but it can only be reduced via dilution.

As for the correct dose for the chlorine, you want to add chlorine so that you always maintain an absolute minimum FC level that is 7.5% of the CYA level. An easier and safer target is an FC level that is at least 10% of the CYA level. For now with low CYA just keep adding what you've been doing. As you get CYA in the water and get to 30 ppm CYA, then you'll just maintain a 3 ppm FC level. You'll probably use Cal-Hypo as your source of chlorine and just keep an eye on the CH level as you seem to have no other choice. It's easier to dilute the water to keep the CH level lower since it's normally at around 300 ppm so a 10% dilution is 30 ppm compared to trying to keep CYA lower where getting to even 100 ppm (which is high) a 10% dilution only reduces this by 10 ppm. The best approach is to use chlorinating liquid or unscented bleach as this adds neither to CH nor CYA, but that is not a realistic option for you.

Another alternative that is more expensive would be to use Trichlor tabs/pucks in a feeder, use pH Up to keep the pH from dropping, and use an algaecide (PolyQuat 60 or a phosphate remover) to prevent algae since the CYA will climb and you won't be able to keep the FC proportionately higher from the Trichlor. This is convenient because you don't have to add chlorine every day, but it requires more chemicals to prevent algae growth.

As for the acid, don't worry about that as you don't need it at this point. If you get a good test kit, it will give you an idea of how much acid you need to add to adjust pH. For an approximation, you can look at The Pool Calculator .

Richard
jemae
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Postby jemae » Sun 20 Apr, 2008 02:05

thank you for the info. Very good. I've visit some of the online pool store from the US but they don't send it to Malaysia. I will try to get a good test kit soon. As for the current reading:
total hardness : 80
free chlorine: 0.5 to 1
total chlorine: max 1
total alkaly: 80
ph: 7.2

All this reading has been very constant since i started my pool.

I have read the posting of the guy fr Malaysia. Keep a look out, in will probably post under the introduction soon under same user name.

As for now, i will probably continue what i've been doing as for your advice until i can get a good test kit.

Thanks again for your help.
chem geek
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Postby chem geek » Sun 20 Apr, 2008 12:33

Since your Total Hardness is so low your Calcium Hardness is even lower. You didn't say if your pool was vinyl or fiberglass or plaster/gunite. If it's plaster/gunite or has tile with grout exposed to the water, then you need to increase the Calcium Hardness (CH) and can most easily do that by using Cal-Hypo as your source of chlorine since it seems that your pool store does not have Calcium Chloride (which is crazy!). It also seemed that your Cyanuric Acid was low -- if the pool store has pure CYA, then you can get some and put it in a sock or panty hose that you hang over the edge so it is in a return flow (it will dissolve in a couple of days that way). Otherwise, you can get Dichlor as another source of chlorine since that will add to CYA.

How long have you had this pool? 240 grams (8.5 ounces) of 65% Cal-Hypo in 15,000 gallons would raise the FC by 2.7 ppm and the CH by 1.9 ppm. So your CH should be climbing by almost 60 ppm per month so you couldn't have had the pool that long to measure the low Total Hardness you are measuring.

Maybe there is another pool store in Malaysia that has Calcium Chloride for raising the calcium hardness. Either that or there are no plaster/gunite pools there! Without enough calcium in the water, the plaster can dissolve -- that is, it can get etched, pitted, rough, break down. If your pool has a vinyl liner, then you don't need to worry about the calcium level. If it's fiberglass, then it depends on the gel-coat that is used (if it has a backing of calcium carbonate).

Richard
jemae
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Postby jemae » Sun 20 Apr, 2008 22:40

Sorry i didn't mention it earlier, my pool is inground concrete and i use normal mosaic. That is why I'm a bit worried about water hardness.

I'm going to the local pool store tomorrow, they said i should change to tablet which is about 90% chlorine for a while. I don't know what it is yet.

That is the problem I faced here, to get calcium chloride also is difficult. I will let you know the soonest.

The ph also start climbing since I put about 2 kg of household salt. (Again following their advice to increase hardness). It is about 7.5 now. Now, can i add hyrochloric acid? Lowering the PH and at the same time increasing the stabilizer?

Thanks

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