No Chlorine

[67corvette]

I have a 40K gallon vinyl liner pool. I have never had this problem before. These are my latest readings by the pool store and I have a Taylor K-1005 test kit. TDS 900 CYA 100 Tot Chl 0 Free Chl 0 ,PH 7.2, Tot Alk 150 Hardness 155, Copper 0, Amonia 1.0. Saturday I added 8 gallons of liquid shock 12.5% sodium hypochlorite. After 4 hours I tested water and chlorine was 10. Next morning I check pool and 0 chlorine. I went to pool store again today and they said to fill my chlorinator up turn it to full open, add 8-10 gallons fo the liquid shock again. I said what if it goes back to zero again. The answer was buy more liquid shock. The said I have to break the demand. This has been going on for almost a month.

[PoolDoc]

Yeah.

I can make a pretty good guess about what's going on -- but move past guessing, you'll have to collect some info for me.

1. What was your CYA level, when you opened your pool?
2. What was the DATE of that test?
3. What was the DATE of the test above (w/ CYA=100)
4. What sort of chlorinator have you been using?
5. What did your pool water look like when you opened?
6. What does your pool water look like, now?
7. List ALL the chemicals used since opening, both kinds & quantities.

If you'll answer those questions AND will complete our new Pool Chart form, I probably can tell what's been going on. The chart takes about 30 seconds, but will save much more than that.

Pool Chart Entry Form
Pool Chart Results

However, that information probably will NOT change what it's going to take to finish cleaning your pool. Most likely, there are just 2 options. EITHER drain and refill (probably NOT an option with a liner pool!) OR add chlorine till 'it' is gone.

You can answer the question, "how much more will it take?" with a bucket test, but you'll need a K-2006 or a K-1515 to do that test. (See info link in my signature.)

[moblaine]

Where are bucket test instructions found?

[67corvette]

Yeah.

I can make a pretty good guess about what's going on -- but move past guessing, you'll have to collect some info for me.

1. What was your CYA level, when you opened your pool?
2. What was the DATE of that test?
3. What was the DATE of the test above (w/ CYA=100)
4. What sort of chlorinator have you been using?
5. What did your pool water look like when you opened?
6. What does your pool water look like, now?
7. List ALL the chemicals used since opening, both kinds & quantities.

If you'll answer those questions AND will complete our new Pool Chart form, I probably can tell what's been going on. The chart takes about 30 seconds, but will save much more than that.

Pool Chart Entry Form
Pool Chart Results

However, that information probably will NOT change what it's going to take to finish cleaning your pool. Most likely, there are just 2 options. EITHER drain and refill (probably NOT an option with a liner pool!) OR add chlorine till 'it' is gone.

You can answer the question, "how much more will it take?" with a bucket test, but you'll need a K-2006 or a K-1515 to do that test. (See info link in my signature.)

1. I don't know
2. I don't know
3. 6/8
4. In line Hayward
5. Terrible dirty and green
6. Clear no algae looks great
7. 30lbs alkalinity, 30 lbs ph+,20 bags super shock, 34 gal Liquid Chlorine

It is 6/13 today and the pool seems to be holding chlorine. It has been 2 days and reading is 10. The last dose of 10 gal of liquid chlorine has seem to work. The reason I don't know the answers to 1&2 is we have 4 pool stores in our area and the first two I went to didn't even tell me about CYA. I started to do research on the internet and learning a little about pool chemistry. So before I found your site I had ordered a K-1005 and amonia kit. BTW my amonia level was 8+. Today's readings Chlorine 10 PH 7.5 Alk 170 Hardness 160 Amonia 0 CYA 55.

Pool looks great. I will look at the kits you suggest.

Going forward. Do I use a powdered dichlor weekly or a liquid or not at all unless reading is below 2?

[Watermom]

If your CYA reading is at 55, then you really don't want to use the dichlor. It is stabilized which means it adds CYA as well as chlorine. A CYA of 55 is high enough. Just stick with using bleach or liquid pool store chlorine. Since you have a large volume pool, if your pool store has large carboys of either 10% or 12.5% sodium hypochlorite (which is the same stuff as bleach but at a higher concentration -- bleach is 6%), that might a good choice for your pool if you can get it at a good price. It will cut down on the number of jugs of bleach you have to deal with. (By the way, you also don't want to use any trichlor pucks as they also have CYA in them. So, you won't want to use your chlorinator.)

Your numbers look pretty good except that we don't know the CC (combined chlorine) reading which is also important to know. Do yourself a favor and get the K-2006 or 2006C Ben suggested above. It will test all the things that are important. Ditch the test strips. We call them 'guess strips' because they aren't very reliable. Since the K-2006 has to be ordered online, you need something to use in the meantime. See if your Walmart has an HTH 6-Way kit (NOT test strips). If not, at the least, get an OTO/Phenol Red (yellow and red drops) kit. You need to be testing your pH and chlorine every day and adding enough chlorine so that you stay between 3-6 ALL the time. If you dip lower, you risk an algae bloom. Read the Best Guess Chlorine Chart in my signature below for more info.

One other thing I want you to do. Test the chlorine level after the sun is off the pool. Then, test it again the next morning within 2 hours of sunrise. Report back how much chlorine you lose overnight.

EDIT -- Upon rereading your post, I see that you are using 12.5% chlorine. That is a good idea for such a high volume pool. Stick with that. I also notice that in your first post you list a volume of 40K but on the Pool Chart, you list 32K gallons. Which is correct?

[67corvette]

My pool measures 20x44. If you measure the water it is really 3 ft of water so I figured the average is about 4.5. I have an 8 ft dept by the hopper.

[Watermom]

Then, I'm getting just under 30,000 gallons for your volume if your average depth is 4.5 ft.