What is the grey powder like stuff at the bottom of my pool?

[poolhomeschool]

Hello all,

I am a new pool owner, hope to get some help. I started to open the pool by myself early June in NYC because no contractor would come out to open. I am a new owner to this pool, when I opened the pool there was only 1/3 water in the pool, And looked greenish. I shocked it and it was all clear, then I backwashed the filter because I was worried the green stuff get stuck in the filter.

Then I went and got the test kit, everything was low. So I added chlorine tablets, calcium hardness. And have very low chlorine reading. I was told by the pool store that I need stabilizer so I added it and increased it to 40. Then it still didn’t read any chlorine. Someone told me I have chlorine lock. The pool store said to check phosphate, and it came back in the 2000-3000. I added the phosphate removal and it still doesn’t real chlorine. Then I added a gallon of chlorine, that seems to fixed the problem and I have stable reading ever since.

Now I have new problem. I see grey powder like stuff at the bottom of the pool. When I brush it dispersed and can’t see it, but after sometime it will show up again. It seems no matter how long I run the filter and vacuum it will help. I see the grey stuff at the bottom every morning when I stop the pump. Yesterday I backwashed the filter and started from brand new and raised the Free chlorine and total chlorine level to 5.

Also, I see bluish brown metal flaks when I Vacuum. I think it could be from the water heater.

I brush the pool twice a week and use the pool twice a week with 4-5 people in it. I maintain it with Clorox extra blue and just recently started using Natural Chemistry pool perfect and phos free.

The current reading

calcium hardness: 250
CYA: 100 (I raised to 40, and it raised on it’s own to 100, so I stopped using the 3 inch chlorine tablets for now.)
PH: 7.4
Alkalinity: 100
Total chlorine: 5
Free chlorine: 5

What am I doing wrong? It does have some pollen flowing around in the air, but what concern me is that it’s not green looking but it’s grey. I don’t see any algae growing, no green stuff by the ladder or wall.

 

[poolhomeschool]

BTW I leave the pool temperature around 80F. I have 2 toddlers and that the temperature that they feel comfortable at. Anything lower will make them shiver. Maybe when hotshot summer come I can lower the temperature, but now it’s not too hot outside. 80s in the afternoon and high 60s-70 at night or early morning.

 

[MITBeta]

That grey stuff is probably dead algae, which means there's more live stuff where that came from.

 

[poolhomeschool]

That grey stuff is probably dead algae, which means there's more live stuff where that came from.

Thanks for your respond. Could it be DE powder from my filter as well? How do I find out if it’s DE powder or dead algae? Thanks again.

 

[poolhomeschool]

I forgot to add that when I added the 1 gallon of the chlorine, I think I did the SLAM without knowing it. Because we my reading at that time were TC 5 and FC 1 before adding the whole gallon. I was frustrated and just pour the whole bottle. The water was clear befoe adding the Chlorine tho. I am very confused. Still confused.

Since then I am able to keep up. But just found out my minimum FC should be 7.5 if I have CYA 100.

 

[poolhomeschool]

I am adding pictures so some of you can tell better. It’s darker in the picture but in real life it’s a dark grey to light grey color. Once I brush it disperse. I brushed this morning so there are not a lot. I see patches here and there in the pool.

 

[mknauss]

I think I did the SLAM without knowing it.

Read SLAM Process. The M is for Maintain. You Maintain your SLAM level FC unitl you pass three specific criteria.

You say a CYA of 100, that takes a SLAM level FC of 39 ppm.

 

[poolhomeschool]

Read SLAM Process. The M is for Maintain. You Maintain your SLAM level FC unitl you pass three specific criteria.

You say a CYA of 100, that takes a SLAM level FC of 39 ppm.

I know I had 30-50cya then. And the whole gallon of chlorine didn’t go away for 4 days. If I did the math correctly with the omega brand liquid shock I bought, it would be above 60 ppm for FC. Ouch...

Since then I was able to match the FC with TC. And I added a bag of shock from Clorox xtra blue... and 3 inch tablet....to maintain weekly for 3 weeks. So I end up With CYA 100. I suspect these product is what caused the spike in CYA, that why I stopped it and started using liquid chlorine and pool perfect with phos free.

please let me know if I am doing anything wrong.

 

[BadDogPSD]

What test kit are you using?
Since Clorox pool products tend to add a bunch of other stuff you don't want in you pool, most of us stay away from Clorox stuff. Any chlorine that says 'stabilized' will increase you CYA levels. The higher your CYA, the more chlorine you need to kill the organics in your pool. 30-50ppm is where you want your CYA, (higher for salt pools). Once CYA is in your pool water, you can only lower the levels by water replacement (drain & refill)
Liquid chlorine or liquid pool shock is what the TFP methods use.
For the most part, all you need is liquid chlorine and muriatic acid to maintain your pool.

 

[poolhomeschool]

What test kit are you using?
Since Clorox pool products tend to add a bunch of other stuff you don't want in you pool, most of us stay away from Clorox stuff. Any chlorine that says 'stabilized' will increase you CYA levels. The higher your CYA, the more chlorine you need to kill the organics in your pool. 30-50ppm is where you want your CYA, (higher for salt pools). Once CYA is in your pool water, you can only lower the levels by water replacement (drain & refill)
Liquid chlorine or liquid pool shock is what the TFP methods use.
For the most part, all you need is liquid chlorine and muriatic acid to maintain your pool.

Thank you. I am currently using pool master 5 ways test kit and I have test strip from HTH and Clorox. The test strip can read up to Chlorine level up to 10 and the pool master only up to 5. just ordered a liquid test kit to test CYA. I currently can only test CYA with the test strip. It’s between 50 to 100. Because the color is very close to 100 so I am guessing it’s reaching 100, definitely higher than 50. The result is the same with 2 different brands of test strip.

Can I try to let the CYA becoming lower on its own instead of replacing the water, like backwashing the filter when needed and splash from swimming etc?

would you happen to know why I get the grey power like stuff at the bottom of my pool? Some one suggested it’s dead algae and the 3 pool stores told me it’s DE from my filter, some other told me I need to call for service. I just don’t know what I should do. The water is clear other wise.

I just want to make sure it’s safe for my kids to get on the water. Since they are toddlers, they swallow water in the pool from time to time. Isn’t DE dangerous...?

 

[BadDogPSD]

Have you read this?

Maintenance and Cleaning of Pool Filters

Maintaining your swimming pool filter system is important. Learn how to clean and maintain your pool filter at low cost & enjoy a Trouble Free Pool.

www.troublefreepool.com

I don't think DE is harmful as I've seen food grade DE for sale, but it would be best to know for sure what it is.
Have you read & watched the information in PoolSchool?
In order for us to help you, you'll need to get a good test kit, the TF-100 is the best, the Taylor K-2006C is also very good. These kits allow you to perform the correct tests to know exactly what's going on with your pool water and what to do following the Trouble Free Pool (TFP) methods.

 

[BadDogPSD]

You could do an overnight chlorine loss test (OCLT). Test your chlorine level in the evening after sunset, and test again in the morning before sunrise. Any loss of chlorine greater than 1ppm indicates you have algea.
I'm not sure if your test kit is accurate enough though...

 

[poolhomeschool]

You could do an overnight chlorine loss test (OCLT). Test your chlorine level in the evening after sunset, and test again in the morning before sunrise. Any loss of chlorine greater than 1ppm indicates you have algea.
I'm not sure if your test kit is accurate enough though...

I just canceled my order from amazon and ordered the TF100 test kit. When I get it I will update. If I do have algae then do I have to SLAM or just shock?

I read that with CYA 100 I need to keep the FC minimum at 7.5 and targe at 11. So I just added 40oz to reach that. I don’t have an acute test kit to test now, but last few days have been hot in NYC, and the reading was at 5 for the last few days.

 

[poolhomeschool]

Have you read this?

Maintenance and Cleaning of Pool Filters

Maintaining your swimming pool filter system is important. Learn how to clean and maintain your pool filter at low cost & enjoy a Trouble Free Pool.

www.troublefreepool.com

I don't think DE is harmful as I've seen food grade DE for sale, but it would be best to know for sure what it is.
Have you read & watched the information in PoolSchool?
In order for us to help you, you'll need to get a good test kit, the TF-100 is the best, the Taylor K-2006C is also very good. These kits allow you to perform the correct tests to know exactly what's going on with your pool water and what to do following the Trouble Free Pool (TFP) methods.

After reading the article, I found that I should add 80% DE powder, but the label on my filter said 4lbs which is the full amount. Maybe that’s why it’s coming back out. I guess I am doing everything wrong... but why the label does not instruct people the right way is beyond my understanding. Very frustrating. I better check everything from the start.

one thing I haven’t been able to find is that why is my filter blowing air bubbles out when I turn it on every night. It makes my pool look foamy for a min the. It’s back to normal. On occasion it take some time Like 15 second for the filter to start when I turn it on. Maybe the previous owner left me a broken filter or pump?

 

[BadDogPSD]

The bubbles could be an air leak. Do you see air in the pump window? Could also be some of the additives you've put in. Additives could explain the foam as well.
Good choice on the TF-100! You are on the right track. It gets easier. One thing to note, is the TFP is a method of pool care that is well thought out, based on science, and about as simple as can be. Try to stay out of the pool store!

 

[poolhomeschool]

The bubbles could be an air leak. Do you see air in the pump window? Could also be some of the additives you've put in. Additives could explain the foam as well.
Good choice on the TF-100! You are on the right track. It gets easier. One thing to note, is the TFP is a method of pool care that is well thought out, based on science, and about as simple as can be. Try to stay out of the pool store!

Could it be I didn’t close the valve tightly and cause the air leak? There is a very minor leak with the filter where the pool water goes in the filter. The air bubble happened after I backwashed the filter.The foamy stuff also happened after that. I only added DE powder after backwashing.The day before backwashing, I used natural chemistry pool perfect phos free. I would imaging after backwashing the filter, there would be no more of that product? Is air bubble ok?

One thing I also do is that I use skimmer socks. It helps with pollen, dandelion seeds, flaying ants and other insects. I noticed if I take the sock out when the filter is off the stuff flow back to the pool, so the last few days I’ve been leaving the filter ok while I remove the skimmer basket to take off the sock. is that ok? It only takes about 30 second. I don’t even know if it’s ok to use skimmer socks, but without it, it’s not trapping the small insects and specially pollen and seeds, and I still see the cotton like stuff on top of the water every morning. Ever since I used the socks the water looks great.

I just want to say thanks for taking your time to respond and to answer my questions.

 

[MITBeta]

That's algae, not DE. I had this same issue ALL last year thinking it was a leaky filter (which ironically would also plug up once per week...). That stuff would appear every time I shocked.

This year I found TFP and all the algae hiding spots in my pool.

Now I'm nearing the end of my 2nd SLAM (first time didn't find all the algae hiding spots). This morning I have a tiny bit of what you're showing in the picture above. Every morning has been less and less. If it was a filter problem it wouldn't go away.

Does the picture below look familiar?

 

[poolhomeschool]

That's algae, not DE. I had this same issue ALL last year thinking it was a leaky filter (which ironically would also plug up once per week...). That stuff would appear every time I shocked.

This year I found TFP and all the algae hiding spots in my pool.

Now I'm nearing the end of my 2nd SLAM (first time didn't find all the algae hiding spots). This morning I have a tiny bit of what you're showing in the picture above. Every morning has been less and less. If it was a filter problem it wouldn't go away.

Does the picture below look familiar?

Thank you for the picture, yes my look like this as well. I attached a picture. So what do I do now? SLAM? Or should I wait till I get my test kit? Is it safe to swim in it since it’s not out of control? My SLAM need to bring it to 39ppm... is it safe for the pool equipment? Sorry for all these question. I am getting frustrated.

It was more yesterday, and this morning I see less. I think it’s best I wait for the kit and see what is the best combined chloramines.

 

[poolhomeschool]

That's algae, not DE. I had this same issue ALL last year thinking it was a leaky filter (which ironically would also plug up once per week...). That stuff would appear every time I shocked.

This year I found TFP and all the algae hiding spots in my pool.

Now I'm nearing the end of my 2nd SLAM (first time didn't find all the algae hiding spots). This morning I have a tiny bit of what you're showing in the picture above. Every morning has been less and less. If it was a filter problem it wouldn't go away.

Does the picture below look familiar?

I just got the recommended test kit and it show no CC

 

[poolhomeschool]

The bubbles could be an air leak. Do you see air in the pump window? Could also be some of the additives you've put in. Additives could explain the foam as well.
Good choice on the TF-100! You are on the right track. It gets easier. One thing to note, is the TFP is a method of pool care that is well thought out, based on science, and about as simple as can be. Try to stay out of the pool store!

So I finally got my test kit. Does high chlorine level mess up the test? The number I got is completely different than my pool master kit.

FC 15
CC 0
PH 7.8 (was 7.6)
Alkalinity 160 ( was 100)
Calcium hardness 500 (was 250)
Cya 70 ( for this test I only had the test strip before and the color was between 50-100 so I thought I was at 100 that’s why I put so much chlorine in the pool.

So what do I do at this point? Do I wait for the Fc to drop and test again? Is Calcium hardness a concern for vinyl liner pool? Do I have to drop Alkalinity and PH?