Instant Blue Green Suspension/Sludge during Winterizing

[celisup78]

New pool owner as of Sept 10th from house purchase. I think the previous owner used his gut feeling for dosing chemicals. I followed the winterization protocol provided by local pool company after they tested my water. Added 10 lb of Alkalinity Plus (sodium bicarbonate), no issues observed. Circulated for 4 hours, then added second 10 lb bag of Alkalinity Plus.... my pool instantly turned cloudy. I finished the rest of their procedure, adding 2 lb of sodium carbonate and 2 lb of 78% powder shock (pool life turbo shock) with their recommended cycle times in between doses. The clarification did not improve.

Below are the original numbers and the numbers AFTER their treatment. I removed my filter and found it was coated in a blue-green squishy material. The pool company does not know what it is and I do not know how to remove it. I have pics of the blue/green sludge but I am still learning how to upload them. You can squish it between your fingers and it easily washes off with water.

I am trying to identify what is this, how it happened, how I should proceed (clean vs drain/refill), and based on my cyanuric acid, copper levels, etc....is it even worth trying to save this water?

Free Chlorine: 5.7, then 18.48
Total Chlorine: 7.64, then 18.49
pH: 6.3 (lowest they can read), then 6.6
Total Alkalinity: 0, then 49
Calcium Hardness: 119, then 172
Cyanuric Acid: 201, then 193
Copper: 2.6, then 3.0
Phosphate: 7,043 then 2,112
Iron: 0.1, then 0.0

Pool: 11K gal in ground, fiberglass, pentair pump and filter

 

[PoolStored]

Welcome to TFP!!!

Sodium Bicarb should not cloud the pool.
Sodium carbonate can cause these issues.
Can you be supper accurate and recount the actual chemicals, timing and observations of the additions?

On of the foundations of TFP is testing the water yourself. I would order a test kit today. Our recommended kits...Link-->Test Kits Compared

Why do you need your own kit? Pool store testing is notoriously wrong. If we make recommendations based on testing that is inaccurate, we can do MORE damage...we don't want that.

The copper is certainly concerning...that is the one test that will give us some indication we would accept. Do you have a heater?

1. Get that kit ordered,
2. add 5ppm of liquid chlorine per day, NOTHING ELSE.
3. Post up pictures of the slime
4. When the kit arrives, post a full set of results. FC, CC, pH, TA, CH, CYA.
5. Fill out your signature with everything you have.
   1. Create Your Signature - Further Reading

We will get you squared away on next steps...

 

[celisup78]

Yes, I have a heater. The pool store uses some type of analytical equipment to test the water. They syringe some water into a clear plastic disc and place it in the instrument. Attached are pics of the filter cartridge as well as the stuff that I washed out of the filter pleats. What is the chance that the rubber/coloring on the filtering rubber is disintegrating? You can see from the side view of the top/bottom rubber edges are near white and there is white showing on the filter rubber top/bottom pics. Since I am the new owner, I do not know what the filter looked like before this problem instantaneously showed up. Could the fast change in the chemicals caused instant failure of the filter rubber?

 

[JoyfulNoise]

Your copper is off the charts high. 3ppm copper indicates that someone was using copper-containing algaecides or other copper containing products to care for the pool. The blue sludge you’re seeing is the precipitation of copper compounds (oxides and carbonates) out of solution as the pH was increased.

With the CYA and copper levels that high, the water is trashed and you need to basically drain the pool and refill. With a fiberglass pool, you can’t safely drain it without the shell collapsing so you’ll have to do an exchange drain.

Draining - Further Reading

www.troublefreepool.com

Please fill out a signature on your profile with all of your pool’s details and equipment so we don’t have to keep looking at your original post for information.

 

[celisup78]

Thanks. I just updated the sig. Hopefully it appears now.

 

[celisup78]

I was reading last night about the CYA numbers and partial drain/refill seemed to be the best solution for levels that high, 200 ppm of CYA in my case. The previous owner used stabilized chlorine pucks. Guessing the cya came from there. I am not sure about the copper as the algaecide bottles in the shed are "In the Swim" Algaecide and do not list copper on them. I thought maybe the copper came from the heater?

I read the link about the No Drain Water Exchange. For an 11K gal pool, I assume that I will be discharging (and adding) more than 11K gal of water since the water that I will be discharging will eventually contain more and more of freshwater since it is mixing with the old water? Is the only way to know when you are done is when the water numbers are in-spec?

Just to confirm, it is unlikely that this stuff is from the filter rubber? Or even if it is, the pool water needs replaced due to the CYA and copper numbers?

 

[JoyfulNoise]

A lot of stabilized chlorine pucks are “multi function” tablets that contain less trichlor, baking soda, copper salts, and a clarifying agent like zinc sulfate. Continues use of pucks then builds up both CYA and all the other junk as well.

 

[JamesW]

Free Chlorine: 5.7, then 18.48
Total Chlorine: 7.64, then 18.49
pH: 6.3 (lowest they can read), then 6.6
Total Alkalinity: 0, then 49
Calcium Hardness: 119, then 172
Cyanuric Acid: 201, then 193
Copper: 2.6, then 3.0
Phosphate: 7,043 then 2,112
Iron: 0.1, then 0.0

Pool: 11K gal in ground, fiberglass, pentair pump and filter

You raised the TA by 151 ppm.

So, the starting TA was -102, which puts the starting pH at about 2.7, which has definitely corroded the copper from the heater.

A pH of 2.7 is 100,000 times more acidic than a pH of 7.7.

11 lbs of trichlor in a 11,000 gallon pool will:

Raise fc by 110 ppm.

Raise CYA by 67 ppm.

Raise salt by 90 ppm.

Lower TA by 77 ppm.

You need 1.14 lb baking soda per lb of trichlor to offset the TA loss.

33 lb of trichlor will Raise the CYA by 200 ppm.

If the CYA was increased by 200, then the TA would have been lowered by about 230 ppm.

If the TA started at 80 and it got lowered by 230, it would be -150 unless baking soda was added on a regular basis.

If the TA gets to 0, then the pH is 4.5.

If the TA goes below 0, then the pH goes below 4.5.

At a TA of -150, the pH would be about 2.52.

pH = -log_10(0.00002X).

X = Positive value of negative TA.

-log_10(0.00002(102)) - Wolfram|Alpha

Wolfram|Alpha brings expert-level knowledge and capabilities to the broadest possible range of people—spanning all professions and education levels.

www.wolframalpha.com

Copper Questions

I recently acquired a pool maintenance and service business with one quite experienced service/repair tech and one new maintenance tech. So I’m still learning every day and trying to become the resident chem “expert” for the group. Have a customer whose pH is unexpectedly dropping between...

www.troublefreepool.com

Added 10 lb of Alkalinity Plus (sodium bicarbonate)

added second 10 lb bag of Alkalinity Plus

adding 2 lb of sodium carbonate

I have a heater.

11K fiberglass inground pool;

PoolMath

Discover the calculator behind the perfect pool, PoolMath. Dealing with pools has allowed TFP to become the original authors of the best calculator on the net.

www.troublefreepool.com

y=-log(0.00002x), y from 2.22 to 4.5 - Wolfram|Alpha

Wolfram|Alpha brings expert-level knowledge and capabilities to the broadest possible range of people—spanning all professions and education levels.

www.wolframalpha.com

y = -log_10(0.00002 x + 0.0000316228) and y = -log_10(0.00002x) | x = -2 to 100 - Wolfram|Alpha

Wolfram|Alpha brings expert-level knowledge and capabilities to the broadest possible range of people—spanning all professions and education levels.

www.wolframalpha.com

 

[JamesW]

The blue and turquoise precipitates are copper.

With those levels, you would probably also see copper cyanurate, which is a purple color.

Google search results

www.troublefreepool.com

https://www.poolspanews.com/how-to/maintenance/when-pools-turn-purple_o

Avoid Opening Pools to Copper Stains

It's pool opening time in many parts of North America. What a drag to pull off the cover and find a copper stain known as purple haze.

www.aquamagazine.com

 

[celisup78]

Thanks, James. Assuming that I interpreted that data correctly, my pH was very low and was/is certainly impacting the heater. Are you in agreement that the old water needs to come out and all fresh water added? I do not think that there is a chemical fix at this point to remove the copper and CYA as well as the copper salts that have formed in the system. My biggest challenge at the moment is understanding where to pump the old water.

 

[JamesW]

Blue might be copper sulfate.

Turquoise is likely copper carbonate.

Amethyst/purple would be copper cyanurate.

 

[JamesW]

Are you in agreement that the old water needs to come out and all fresh water added?

Yes, but draining involves risk of floating or otherwise damaging the pool, so you need to figure out how to do it safely.

 

[JamesW]

With a starting pH at about 2.7, the water has definitely corroded the copper from the heater.

How badly damaged the heater is is difficult to determine without inspecting the heat exchanger tubes.

Do a full water replacement in a safe way and watch the heater for leaks.

Have you seen any purple stains?

 

[PoolStored]

The pool store uses some type of analytical equipment to test the water.

Don't confuse analytical and precise with accurate. Get your own test...much more accurate and we know we won't do more harm.

Testing_Accuracy.jpeg

• PoolStored
• Sep 16, 2024

For an 11K gal pool, I assume that I will be discharging (and adding) more than 11K gal of water since the water that I will be discharging will eventually contain more and more of freshwater since it is mixing with the old water? Is the only way to know when you are done is when the water numbers are in-spec?

The best way to know is to time your hose. Get a 5 gallon bucket, put your hose in and turn it on. Time 5 gallons. Then, divide your 11K by 5 and multiply that by the time it took to fill 5 gallons...that should roughly give you the amount of time to run your hose. You will need to monitor your sump pump, or add head by putting the hose over a ladder to match output with input.

 

[proavia]

Draining - Further Reading

www.troublefreepool.com

You really need your own test kit.
Test Kits Compared

 

[celisup78]

I'll take a look at the test kit. I went out and looked at the pool after letting it sit for 18 hours without the pump running. Much of the copper salts have settled to the bottom. Is it recommended to vacuum these up? If so, with what type of vacuum? Is it also recommended to treat with a clarifier to drop more of it out of suspension so I can filter it up? I would love to remove most if it before pumping it out.

 

[PoolStored]

Get the kit...it will save you money in the long run.
Do you have a vacuum? Do you have a robot? Can you vacuum to waste?
Do not add clarifier.

Recommended Pool Chemicals

Which should I buy? TFP's recommended pool chemicals are cheap, easy, and won't unbalance your pool water.

www.troublefreepool.com

Non-Recommended Pool Chemicals

These pool chemicals should not be added to your pool. Save your money and frustration and avoid these chemicals!

www.troublefreepool.com

 

[celisup78]

With a starting pH at about 2.7, the water has definitely corroded the copper from the heater.

How badly damaged the heater is is difficult to determine without inspecting the heat exchanger tubes.

Do a full water replacement in a safe way and watch the heater for leaks.

Have you seen any purple stains?

No, I have not seen any purple stains.

 

[celisup78]

Get the kit...it will save you money in the long run.
Do you have a vacuum? Do you have a robot? Can you vacuum to waste?
Do not add clarifier.

Recommended Pool Chemicals

Which should I buy? TFP's recommended pool chemicals are cheap, easy, and won't unbalance your pool water.

www.troublefreepool.com

Non-Recommended Pool Chemicals

These pool chemicals should not be added to your pool. Save your money and frustration and avoid these chemicals!

www.troublefreepool.com

I have the Poolmaster Big Sucker and I have a robot (unsure of the make/model as I am not at home). I dont think I have a big sucker filter bag with fine mesh to capture the salts.

I will have to google what it means to vacuum to waste as I am not sure.

 

[PoolStored]

I will have to google what it means to vacuum to waste as I am not sure.

Post pictures of your equipment pad and we'll tell you if you have the capability...it would be build into your plumbing...