Pool is cloudy - chemistry is perfect, no leaks anywhere! HELP!

[Argosy]

I have this problem for the past couple of weeks and it seems that it is escalating very rapidly. Basically my pool chemistry is as usual. Today's readings are: FC=2.5; PH=7.2; Alkalinity=100; Calcium Hardness=270; Saturation Index=-0.2. The pool is clean, but not very welcoming due to cloudy water. It looks like there is too much air tiny bubbles in the water. I read on TFP that the cause might be a leak in the system, but there are no leaks except a very minor one that is coming from the pump itself. How can I trouble shoot this problem and what could be done. I was thinking to close down the pool next week for couple days to drain it partially and the fill it up with fresh water. That would be my last resort. With the way things are going, I may have to close the pool per city regulations (once the black disk at the bottom of the pool will stop being visible). Maybe someone had similar problem?

 

[Texas Splash]

Sounds like you have a couple issues going on - cloudy water (sign of an algae bloom) and air bubbles (sign of a suction side air leak). Take a look at these two links to help get you started:
For algae: SLAM via Pool School - SLAM - Shock Level And Maintain
For air bubbles: Pool School - Suction Side Air Leaks

Start there and we'll follow-up as you get a chance to read or have questions.

 

[duraleigh]

Welcome to the forum.

What about your filtration? How long do you run the pump. Is it a cartridge filter. When was it last cleaned? Does your psi change? Is there visible debris on the pool floor?

 

[otter86753]

Unless I missed it, you didn't post your CYA level. That is key information to diagnose the issue.

 

[Argosy]

Reading the links...

CYA level is not applicable to this specific indoor pool (not sure why, but in my weekly pool log, under testing CYA says "not applicable" and I don't think we even have a complete reagents to do this test). I will try to perform this test anyway, and if successful, I will post the results

Sand filter, runs 24/7 with Jacuzzi 1.5 horse power pump. I vacuum pool and backwash filter every week. Last time - today! PSI does not change. It is usually 22-24 PSI. There are some visible debris on the pool floor, but no more the usual.

The water comes out milky/bubbly from the outlets. I talked to one of the Maintenance guys and he said that there might be an obstruction somewhere in the system that is causing this.

The whole thing with cloudy pool started about a month ago. I read some info on TFP and went to investigate for potential leak in the system. There was a pin hole on one of the inlet lines. The plumber patched the leak the same day and the clarity started to come back the next day. This lasted for about 3-4 days and then it started to get worst again.

 

[Texas Splash]

You are correct about CYA. It is much different (impacting FC) for an indoor pool since there is relatively no competition with sunlight. Doesn't mean you can't get algae which starts-out cloudy. But your filtration may be an issue as well. It's odd that as you stated, even after a backwash the pressure hasn't changed. That may requires more research or feedback from the forum. I can't imagine a leak contributing to cloudiness though. Air bubbles (suction side) yes; water seepage (pressure side) sure.

I'm curious to see what other experts have to say about possible problems with the filtration system and components within (i.e. laterals). Perhaps there's something there we haven't pinpointed.

 

[Argosy]

After reading Pool School - Suction side air leaks, I am 99% sure I have an air leak somewhere and my main suspect is the O-ring on the pump. I have a feeling it needs replacement. While the plumber will get me the new O-ring, I have a plan to try to shut off the main floor drain for the night and see if the clarity changes by morning. This pool is in the basement, but is above ground. I can walk under the pool deck and all around the pool. Most plumbing is accessible, except the main drain, that goes under ground partially. I want to rule out possible air leak in this suction line.

- - - Updated - - -

The pressure drops from 24 PSI to 22 PSI after backwashing. There are 5 bathers per day on average in the summer and even less then that at all other seasons.

 

[Texas Splash]

You have a HUGE advantage being able to survey your plumbing. That's great.

 

[Argosy]

This is the current state. Note the black disc at the bottom. It suppose to be BLACK and clearly visible. Mine is about to disappear. If that happens, I will have to shut down the pool by law.

 

[Texas Splash]

Have you considered also doing an overnight chlorine loss test per Pool School - Perform the Overnight FC Loss Test (OCLT). If you have organics in the water, that will tell you. Even though the sun doesn't apply to you necessarily, you can still follow the same rules just to be standardized.

 

[Argosy]

Oops. I think I just found the problem. I shut down the suction for the main drain and immidiatly noticed that the pump basket lost all the air inside. Slowly opened the suction back and the pump became full of water/air mixture. Shut it off again and went to the pool deck to see if the jets were shooting clean water and they did. I will leave it like that for the night and we'll see in the morning if it was the cause of the problem.

Now, I have another question. What would be the side effects of having only 2 skimmer baskets filter the water without the deep end drain? I am not sure if our plumber will be able to fix the problem fast. If not, I guess I will have to put a pool vac on the bottom to run with another skimmer overnight. Temporally of course.

 

[jblizzle]

Many pools do not even have a floor drain and they can be kept perfectly clear.

 

[duraleigh]

Oops. I think I just found the problem.

I think you may be only partially correct. Air bubbles are not causing that cloudiness. Contaminants in your water are causing it because you basically have had no filtration for who knows how long. The suction side air leak allowed the pump to drop prime and so, for however long that leak has been present, you have had little if any filtration in that pool.

1. Fix the air leak and make sure your pump is circulating water properly.

2. SLAM the Pool. read "The ABC's of Pool Water Chemistry" up in Pool Schoolnd then follow that by reading the SLAM article. That will clear the pool. Repairing the suction side leak might make you think you have it solved but that's not enough.

What are you using to chlorinate the pool?

 

[Patrick_B]

Knowing the Cya level would be very good to know, but the reason it says it's not applicable, is because it isn't supposed to have any. At least in the US in an indoor pool. Still, depending on what Chlorine sources have been used, there may be some present. A little different situation here with it being commercial, so let us know what you find out. Depending on the Cya, you may have to close it if you do decide to perform a SLAM procedure.

 

[pooldv]

Yes, if you are using dichlor or trichlor products to chlorinate the pool then you could have a problem with high CYA and insufficient chlorine for the CYA level. Chlorine CYA Chart. If there is no CYA in the pool you could benefit by adding 20-30 ppm to buffer the chlorine.

 

[Argosy]

I think you may be only partially correct. Air bubbles are not causing that cloudiness. Contaminants in your water are causing it because you basically have had no filtration for who knows how long. The suction side air leak allowed the pump to drop prime and so, for however long that leak has been present, you have had little if any filtration in that pool.

1. Fix the air leak and make sure your pump is circulating water properly.

2. SLAM the Pool. read "The ABC's of Pool Water Chemistry" up in Pool Schoolnd then follow that by reading the SLAM article. That will clear the pool. Repairing the suction side leak might make you think you have it solved but that's not enough.

What are you using to chlorinate the pool?

We use liquid chlorine. I checked the pool this morning and it was already nice and clean. I put in the pool vacuum near the drain and went to search for the leak. I found a leak very close to shut of valve. The plumber will be able to fix it fast, so I should be good. Turns out this alone was causing the pool to become cloudy, but you also right about poor filtration during past 2 weeks. It was probably not doing a good job with all those air bubbles. I will have the plumber to check the pump as well.

Will post photos of yesterday and today to show the difference soon...

 

[Argosy]

That was yesterday evening.



This is this morning, almost clear!


My temporary fix to filter out the deep end.

By evening I expect it to become crystal clear again!

Will SLAM the pool tonight and will post new photos in the morning...

 

[jblizzle]

You can not follow the SLAM process in one night ... You are welcome to elevate the FC level one time, but don't call that a "SLAM"

 

[tim5055]

Jason is correct. Don't confuse "shocking" the pool with a SLAM. Shocking adds an unscientific amount of chlorine to the pool for a short period of time hoping it will fix things. A SLAM deal with adding a specific amount of chlorine to,the pool and holding it at shock level until testing shows that the water has been cleared of all the bad stuff growing in it.

 

[pooldv]

More here, Pool School - SLAM - Shock Level And Maintain