Excessive Chlorine Consumption

[jetmecha320]

I have had a problem this year maintaining any type of FC levels in my pool. I have shocked and overshocked my pool in the evening and by morning my FC levels are at 0. I also run the filter 24 hrs with 3 in tabs in the skimmer and still there is no FC readings. I have been using quite a bit of shock and tabs to no avail. I have not had an algae problem at all. The water has been cloudy at times but a flocculant has taken care of that. I have been to my local pool store and had my water tested and was told my nitrates are high. The have me shocking my pool quite a bit over the next few days with calcium hypo-chlorate. The have said this will destroy the nitrates. I have read on line that the only way to get rid of nitrates is to drain and re-fill. Also if the nitrates were high wouldn't I have an algae problem? I have an 27 foot above ground pool with a capacity of around 1,500 gallons my other important readings are;
FC- 0
PH- 7.4
ALK- 100
CYA- 50
Hardness- 200
I use a Taylor test kit for all my testing. my Total Chlorine and Combined Chlorine are also at 0.
Could nitrates be the cause of the chlorine demand, and if so how are they removed from the pool?
If nitrates are not my problem, What else is there? Any advice would be appreciated

 

[Smykowski]

Welcome to the forum!

Nitrates are nonsense. Most of us here have no idea what our nitrate levels are.

Your FC is not holding because you likely have something in your pool that is consuming it. That is, the FC is going away because it's doing its job. Shocking the pool will fix the problem, but you need to follow our shock PROCESS, not just put bag after bag of product with the word "shock" on the label. You also need to stop using dry chlorine. Your CYA is fine where it is, but cal-hypo will drive your CH numbers through the roof. Switch to liquid.

What are your CC levels?

I'd spend some time reading pool school, then get to work on the shock process.

 

[jetmecha320]

Combined chlorine is also unreadable. There is no smell of chlormaines.
Where is the shock process mentioned above, thanks

 

[Patrick_B]

Hey Jet, Welcome to TFP. Could you please clarify your pool volume. I'm thinking 1500 gal was a typo and you are missing a digit. At 27 ft wide, you are far over 1500. Also, does your kit test total Chlorine as well? Either way you have something consuming your FC and you should shock according to the info in the Pool School. As stated it's a process and not an event.

Edit: Sorry, looks like we were posting at the same time. What do you mean the CC is unreadable? You have no indication of any?

 

[Butterfly]

Where is the shock process mentioned above, thanks

Pool School, white button top right of each page.

Welcome to the forum

 

[jetmecha320]

Sorry about the typo but my pool volumne is 18.500 gals. My test kit does test for combined chlorine. The first test is for Free Chlorine, then for Total Chlorine
TC-FC=CC , 0-0=0. After I shock the pool I will get a high reading on the test kit but in the mroning when I test for FC TC and CC I have less than what I can read on my test kit. So I'm losing all a lot more tham 1ppm overnight.

 

[duraleigh]

Follow the advice of the responders above. read "How to Shock Your Pool" up in Pool School

 

[Richard320]

You might have ammonia. Check this thread and also try the search box for ammonia for more.

Bottom line: it'll take a whole lotta chlorine. And a proper test kit that actually measures CC, not just calculates it.

 

[jetmecha320]

I will follow your shock procedure for the next couple of days and let you know how it goes. Thanks for all the good advice

 

[duraleigh]

I will follow your shock procedure for the next couple of days and let you know how it goes. Thanks for all the good advice

It may take a little longer than that but, if you are committed, it will work. If you are not committed, it probably won't.

 

[Patrick_B]

Sorry about the typo but my pool volumne is 18.500 gals. My test kit does test for combined chlorine. The first test is for Free Chlorine, then for Total Chlorine
TC-FC=CC , 0-0=0. After I shock the pool I will get a high reading on the test kit but in the mroning when I test for FC TC and CC I have less than what I can read on my test kit. So I'm losing all a lot more tham 1ppm overnight.

No need to be sorry. I knew it was a typo/mistake. No worries...just get the FC up to shock level and KEEP it there. As Dave said, stay persistant and you will overcome. Two days will be the start, and perhaps it will take many, many, more. I suspect it will be several at best.

 

[jetmecha320]

Shocked the pool last night and took a reading of my chlorine levels this morning. To my surprise I had a reading of FC of 2.0. it was quite a drop from last night but it is the first time in a week that I was able to obtain a reading in the morning.

 

[Butterfly]

Shocked the pool last night and took a reading of my chlorine levels this morning. To my surprise I had a reading of FC of 2.0. it was quite a drop from last night but it is the first time in a week that I was able to obtain a reading in the morning.

You have burned thru whatever it was (ammonia prob) and are now on further down the road to recovery!

Continue to follow the shock process as outlined in Pool School and let us know how it is going.