Added Chlorine Shock and Muriatic acid to Cloudy Pool, FC still 0.6

giant_donut

Well-known member
Mar 16, 2021
51
Austin, TX
Pool Size
20000
Surface
Plaster
Chlorine
Salt Water Generator
Hi All,

Yesterday I noticed my pool was looking cloudy and fortunately I have a pool company that comes to service the pool. I have a Taylor K2006 Test Kit and tested the pool yesterday before it got serviced.
FC = 0.2 ppm
CC = 0.4 ppm
pH = 8
A = 90-100
Calcium Hardness = 650
CYA = 60

The pool guy came today and had similar results as I. He added 1 gallon Blue Whale Shock Chlorinator (12.5%) and 1 gallon Blue Whale Muriatic Acid (33%) while the pool pump was running.

It's been about 5 hours and the pool is still cloudy. I tested again and the results were as follows:
FC = 0.6 ppm
CC = 1.2 ppm

I did not test for pH to see if it reduced.

Question: I was expecting the FC to go up to at least 5ppm. Should I add another gallon of liquid chlorine (12.5%)? Why did the CC go up from 0.4 - 1.2 ppm?
 

JohnT

Admin
Mod Squad
TFP Expert
Apr 4, 2007
9,930
SW Indiana
Pool Size
21000
Surface
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Chlorine
Liquid Chlorine
Welcome to TFP!

In 5 hours you’d easily use up a gallon of chlorine with a cloudy pool. Check after an hour and add to reach the SLAM level as described in Pool School.
 

magiteck

Gold Supporter
May 20, 2020
421
Neenah, Wisconsin
Pool Size
13600
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Vinyl
Chlorine
Liquid Chlorine
At a CYA of 60, your FC should never go below 5ppm. FC/CYA Chart

In a 33,000 gallon pool, a gallon of 12.5% would only add 3.8ppm. So the gallon that was added didn’t even get you to the minimum you should be at (if the water was clear). PoolMath

Given that you have cloudiness, and have fallen below the minimum, you need to complete a SLAM Process.

To bring your FC up to SLAM level of 24ppm in a 33000 gallon pool, you’re going to need to add just over 6 gallons of 12.5%. Then, you need to test multiple times daily and add more to stay at that level until the water is clear. Once the water is clear, perform an Overnight Chlorine Loss Test, and once you pass the pool should be good - you’ll just need to make sure to keep the FC above 5ppm, ideally between 7-9.

The CC is going up because the small amount of FC is immediately being consumed by algae. The CC is the byproduct of that and will also clear up with the SLAM.

I suggest you read through ABCs of Pool Water Chemistry for more of the science behind our recommendations here.

Oh, and welcome! :)
 

giant_donut

Well-known member
Mar 16, 2021
51
Austin, TX
Pool Size
20000
Surface
Plaster
Chlorine
Salt Water Generator
At a CYA of 60, your FC should never go below 5ppm. FC/CYA Chart

In a 33,000 gallon pool, a gallon of 12.5% would only add 3.8ppm. So the gallon that was added didn’t even get you to the minimum you should be at (if the water was clear). PoolMath

Given that you have cloudiness, and have fallen below the minimum, you need to complete a SLAM Process.

To bring your FC up to SLAM level of 24ppm in a 33000 gallon pool, you’re going to need to add just over 6 gallons of 12.5%. Then, you need to test multiple times daily and add more to stay at that level until the water is clear. Once the water is clear, perform an Overnight Chlorine Loss Test, and once you pass the pool should be good - you’ll just need to make sure to keep the FC above 5ppm, ideally between 7-9.

The CC is going up because the small amount of FC is immediately being consumed by algae. The CC is the byproduct of that and will also clear up with the SLAM.

I suggest you read through ABCs of Pool Water Chemistry for more of the science behind our recommendations here.

Oh, and welcome! :)
Can I do the SLAM tonight (overnight) and have the pump run through the night? In the morning I'll check the results again and follow the process again.
 

magiteck

Gold Supporter
May 20, 2020
421
Neenah, Wisconsin
Pool Size
13600
Surface
Vinyl
Chlorine
Liquid Chlorine
If you’ve already got the chlorine, I’d say go ahead and get started. That’ll give the chlorine a head start on the algae before it’s fighting the sun as well. Just make sure to bring it back up to SLAM level in the morning and then re-check and maintain every few hours (or as often as practical.)
 
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giant_donut

Well-known member
Mar 16, 2021
51
Austin, TX
Pool Size
20000
Surface
Plaster
Chlorine
Salt Water Generator
If you’ve already got the chlorine, I’d say go ahead and get started. That’ll give the chlorine a head start on the algae before it’s fighting the sun as well. Just make sure to bring it back up to SLAM level in the morning and then re-check and maintain every few hours (or as often as practical.)
Yeah i picked up from lowe's and got pool essentials chlorinating liquid (10%). I only have 6 gallons so i'll get some more in the morning to maintain it.
Thanks for everyone's help!
 

YippeeSkippy

Mod Squad
LifeTime Supporter
Jan 17, 2012
16,075
Evans, Georgia
A SLAM process is not a one time addition. I would say you need to re-test and dose at *least* 3x a day. The more often you keep with it, the faster it will go.

I'd also wonder why I'm paying a pool tech who let my pool get in such poor condition? Your CH is pretty dang high, your pH is high, your FC is way too low and your CYA too high for a pool that isn't running a SWG. Is the pool company using pucks??

Maddie :flower:
 

giant_donut

Well-known member
Mar 16, 2021
51
Austin, TX
Pool Size
20000
Surface
Plaster
Chlorine
Salt Water Generator
A SLAM process is not a one time addition. I would say you need to re-test and dose at *least* 3x a day. The more often you keep with it, the faster it will go.

I'd also wonder why I'm paying a pool tech who let my pool get in such poor condition? Your CH is pretty dang high, your pH is high, your FC is way too low and your CYA too high for a pool that isn't running a SWG. Is the pool company using pucks??

Maddie :flower:
Yes, the pool company is using chlorine pucks...
 

magiteck

Gold Supporter
May 20, 2020
421
Neenah, Wisconsin
Pool Size
13600
Surface
Vinyl
Chlorine
Liquid Chlorine
Yes, the pool company is using chlorine pucks...
Definitely ditch the pucks. Each puck is adding more CYA, which as the FC/CYA Chart shows you means you require ever higher levels of chlorine. You’re already at the upper limits of what we’d recommend for CYA in a manually chlorinated pool — and CYA is only really removed from the water by draining. So you definitely don’t want any more.

Fire the pool service, switch to liquid chlorine (or invest in a Salt Water Chlorine Generator), stick to TFP for guidance and you can have a balanced trouble-free pool for a few minutes a day (or less, if you go the chlorine generator route). Oh, and we’re free, unless you want to Become a TFP Supporter. :)
 
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YippeeSkippy

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Jan 17, 2012
16,075
Evans, Georgia
Oh dear, that's gonna set you up for some problems in short order.

Each "puck" or stick that contains chlorine *also* contains either CYA stabilizer or calcium. Both build up and cause problems independent of the chlorine itself. Too much CYA requires you to keep your daily running FC level higher. Too much calcium causes scale to develop on your walls.

We recommend the use of Liquid Chlorine or a Salt Water Chlorine Generator as a rule. Have you read any of the Pool School articles yet? Let's start here....>
ABCs of Pool Water Chemistry
Recommended Levels
FC/CYA Chart

Maddie :flower:
 
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giant_donut

Well-known member
Mar 16, 2021
51
Austin, TX
Pool Size
20000
Surface
Plaster
Chlorine
Salt Water Generator
Oh dear, that's gonna set you up for some problems in short order.

Each "puck" or stick that contains chlorine *also* contains either CYA stabilizer or calcium. Both build up and cause problems independent of the chlorine itself. Too much CYA requires you to keep your daily running FC level higher. Too much calcium causes scale to develop on your walls.

We recommend the use of Liquid Chlorine or a Salt Water Chlorine Generator as a rule. Have you read any of the Pool School articles yet? Let's start here....>
ABCs of Pool Water Chemistry
Recommended Levels
FC/CYA Chart

Maddie :flower:
Yeah, i've been keeping busy by reading the ABC's and the recommended levels. I only got around to finally getting my own test kit because I wanted to learn so that I can maintain the pool myself. The pool servicing has been good thus far but now I'm pretty annoyed with the levels. I didn't know the ins and outs of chlorine tablets versus liquid chlorine but now that I'm reading up on it, I'll either fire them or ask them to start using liquid chlorine. Appreciate everyone's replies thus far.

Quick question about the SWG. We do have the hookup for it but it needs to be replaced. We have a waterfall feature and I've read in other areas that the SWG may cause damage to the waterfall and our pool heater (pentair). The house is still under warranty so I may be able to get the SWG replaced at a nominal cost.
 

mknauss

Mod Squad
TFP Expert
Bronze Supporter
May 3, 2014
37,257
Laughlin, NV
Pool Size
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Surface
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Chlorine
Salt Water Generator
SWG Type
Pentair Intellichlor IC-40
SWG may cause damage to the waterfall and our pool heater (pentair)
The low level of salinity in a saltwater pool has no effect on those items. Low pH, however, does effect those items.

Replace the SWCG. You need a unit rated for a 60K pool. Only Pentair and Circupool make them for that size.
 

giant_donut

Well-known member
Mar 16, 2021
51
Austin, TX
Pool Size
20000
Surface
Plaster
Chlorine
Salt Water Generator
Update as of the morning:
Last night I had removed the tablet floater for the chlorine pucks, added 6 gallons of LC (10%), and had the pump running overnight. l checked FC this morning and it is at 24ppm. Water is starting to clear up. Bought another 12 gallons of Liquid Chlorine (10%) and will add accordingly to maintain this level. Will test again in a few hours for FC / CC and follow the steps as listed in SLAM. Plan is to conduct OCLT when the CC is <0.5ppm and water is clear.
 

giant_donut

Well-known member
Mar 16, 2021
51
Austin, TX
Pool Size
20000
Surface
Plaster
Chlorine
Salt Water Generator
Will do. Just tested a few mins ago.

Around 12pm I had tested again. The FC went down to 22ppm and CC was at 0ppm. Used pool math and that recommended to use 58 oz of LC (10%) to bring it back up to 24ppm.

At 4pm I tested once again. The FC is up at 25ppm (think I added 64 oz of LC) and CC is 0ppm. Tested pH (though I read it might be inaccurate during SLAM) and it was 7.2 (pool guy had added 1 gallon of Muriatic acid yesterday).

I'll maintain at this level for another few hours and test just when the sun is about to go down (7:30pm). Will log results. Been brushing, raking, and skimming all the leaves while having the polaris pick up additional debris on the bottom.

Pool is getting clearer! Thanks TFP!
 
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wireform

Silver Supporter
In The Industry
Aug 15, 2017
2,115
Spring Valley, NY
I'd also wonder why I'm paying a pool tech who let my pool get in such poor condition? Your CH is pretty dang high, your pH is high, your FC is way too low and your CYA too high for a pool that isn't running a SWG. Is the pool company using pucks??

Maddie :flower:
And why a gallon of Blue Whale Muriatic Acid (33%) with the ph at 8. Fire him yesterday. Tomorrow is too late.
 
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giant_donut

Well-known member
Mar 16, 2021
51
Austin, TX
Pool Size
20000
Surface
Plaster
Chlorine
Salt Water Generator
And why a gallon of Blue Whale Muriatic Acid (33%) with the ph at 8. Fire him yesterday. Tomorrow is too late.
Yeah I agree. The fact that I just paid for LC on top of what I pay these guys is ridiculous. The pool guy thought 1 gallon of LC would do the trick and he wasn't going to come by for another week. Clearly 1 gallon of LC was not enough and the fact that he added 1 gallon of muriatic acid was way more than needed (based on what pool math said should be 33oz).

I need my wife to be onboard this decision as well and after I show her these posts we'll be in agreement to fire them and will maintain it ourselves. At first we were intimidated at maintaining the pool but with TFP and its resources, it's been fun to learn and see the results. Plus I'd rather take ownership and pride of maintaining the pool myself.
 

giant_donut

Well-known member
Mar 16, 2021
51
Austin, TX
Pool Size
20000
Surface
Plaster
Chlorine
Salt Water Generator
You’re doing great. Once your water looks like this your wife will hopefully come around in a hurry. :)
Oh whoa! Those are some crystal clear pools. I’ll be very happy if mine comes to look like those. Hopefully will post a pic in the next day once all algae is gone.
 

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