White gritty scale

[Wapak]

Hello, I am new here and have a problem with a white gritty substance on my pool walls no one can seem to figure out. Hoping to get some answer to try to correct it.

I have a 16' X 48' in ground, vinyl liner pool. I opened the pool on May 20th. At opening was extremely dark green. i have shocked it continuously since then about every 2 days, starting with calcium based granules, then switching to sodium based liquid.

The algae is all dead, and the water is a light blue with alot of cloudiness, however every day it clears up more. i run my sand filter 24/7 and back wash about once a day.

A white grit, kind of like 'scotch tape with white sand' in it, is coating my entire pool walls and bottom. It is really abrasive in spots. It is somewhat clear, you can see through it, but I can only get very small spots off. I have scrubbed, even scraped with a rubber squigee and can only get off a very little bit at a time and it is coating my entire pool.

I have never had this issue in 7 years. I went to a local pool company and they keep giving me different chemicals to try, but I dont think they know what it is. my water is clearing and for the first time, i can see the bottom, just this bad white grit issue is all thats left.



Here are my today water test readings:
free aval chlorine: 5.72
Tot chlorine: 10.31 (just shocked again last night)
combined chlorine: 4.59
tot alkalinity: 170
ph: 6.9 (was balanced to 7.5 4 days ago)
cal hardness: 342
cyranic acid: 14
total dissolved solids: 1280
saturated index: -0.4

heres what they told me today:

add 1.5 gallon of muratic acid
add 40oz enzymes (they think it may be white water mold??)
scrub walls

then, add ph increaser

then shock again.


Can anyone out there help me?? i am desperate and i dont think its white water mold, I know there must be a solution for this,

[PoolDoc]

FC=5.72 ppm??

Must be going to a BioGuard dealer. There are no consumer or commercial grade mechanism for detecting chlorine levels to 0.01 ppm, but BioGuard is notorious for terribly erratic and often very inaccurate test results that their 'program' presents as super-accurate.

What that list of numbers tells me is, we have NO idea what's in your pool. That sort of computerized bogus testing is sometimes reasonably accurate (5.72 actually should be 4 or 4.0) and sometimes completely bogus (CYA = 0 or 50, instead of 14). We have no way to know, till you test with a reliable test kit.

By the way, you can probably confirm the identity of your scale, by scraping off a bit, and putting in in a clear glass (a wine glass would be perfect) with a bit of white vinegar. If it bubbles, it's calcium carbonate scale. If it does NOT bubble, cover the glass with Saran wrap, and wait till tomorrow. If the scale bits have dissolved . . . .it's calcium carbonate (limestone) scale.

OK, we can't do ANYTHING till we know what's in your pool. Do NOT use the chemicals you were given. (Don't take them back, yet, either. You may need them.) Instead, do this:

1. Get an OTO(yellow drops)/phenol red testkit. If possible, get the excellent Taylor-made HTH 6-way drops kit sold at some Walmarts (and nowhere else!). Check local availability here: HTH 6-Way Test Kit (http://www.walmart.com/ip/HTH-6-Way-Test-Kit/17043668) .

2. While at Walmart get 10 gallons of PLAIN 6% household bleach. Add 2 gallons of bleach this evening, and then each subsequent reading if your OTO test shows less than a strong yellow result the following evening.

3. Measure your pool. 16' x 48' is a VERY unusual size. On Google Maps it looks like maybe an 18x36 with steps. Measure only the main rectangle; do not include the steps. We can use those measurements to get a reasonable estimate of the gallons in your pool. (Most builders and pool stores over-estimate gallons.)

4. Read the test kit page in my signature, and then order a Taylor K-2006. You'll need it.

5. Report your test readings tomorrow. If you can find the HTH kit, report chlorine, pH, alkalinity, calcium and stabilizer. Otherwise, just report pH and chlorine.

6. Use these links to log in your pool info:

Pool Chart Entry Form (http://goo.gl/cNPUO)
Pool Chart Results (http://goo.gl/PXaLu)


By the way, the scale you describe is often deposited by algal & bacterial slime over the winter. Here are a couple of pictures:
https://lh6.googleusercontent.com/-d2tJcMt3AaI/T6b1Gx5037I/AAAAAAAACvE/AjSjAFfe4Z0/s400/sand_algae_01_HHH.jpg -- https://lh6.googleusercontent.com/-deyZ3MI-1P8/T6b1GB7LP-I/AAAAAAAACu8/l3ghrWME_-Y/s400/sand_algae_09_HHH.jpg

[Wapak]

Thank you pool doc for responding so quick! On my way to get test kit and bleach at walmart. I will post my test results once done.

I did the vinegar test, and eventhough th particles were very small, they did bubble. I will post my test results soon.

Thank you, finally i feel like i am dealing with someone who is a pro!

[PoolDoc]

We'll be here!

[BigDave]

...finally i feel like i am dealing with someone who is a pro!
You won't find better advice than Ben's at any price, and he does this for us for free!

[Watermom]

Yeah, but unfortunately it is not free for Ben to run this forum. So, that is why we appreciate all the people who subscribe and also those who purchase products through Pool Forum's Amazon links because the revenue is what enables the forum to stay viable and helping people!

[Wapak]

Ok,

I was able to scrape some of the scale off, it was small particles like ground up chalk. I put it into a wine glass of vinegar, it immediately bubbled, then after about 5 minutes, it was completely dissolved.

You were correct, the actuall size of the pool after I measured it is 16' width, 36' length. I have a 3 ft shallow end that gradually slopes down to a 9ft deep end

I added the 2 gallons of 6% household bleach last night.I forgot to mention that on Sunday, i did add hth clarifier to the pool.

This morning, the water is finally clear enough to see the bottom of the deep end, crystal clear in the shallow end, still cloudy in deep.

I did get an HTH 6 way test kit. This is the first time I have ever used one, but I think I was able to get accurate results, love this test kit!! here was what I have this morning:

Chlorine: Very strong yellow, almost orange color
Ph: 7.2
Alkalinity: 160
Hardness/Calcium: 580
CYA: I am showing 0: I tested this twice to make sure I was doing it right, couldnt make the black dot disappear at all, so i couldnt come up with a ppm number

I hope this is the correct information you needed. If not, let me know.

Tried scrubbing pool walls again last night (i have been doing this everynight since I opened) in hopes to see some scale removal happening, but no luck! still same gritty white stuff covering and stuck to walls

so again, thank you for your help, if you have a solution to remove the scale that I have I cant wait to hear it!

[PoolDoc]

Tried scrubbing pool walls again last night (i have been doing this every night since I opened) in hopes to see some scale removal happening, but no luck! still same gritty white stuff covering and stuck to walls

Stop it! Really, I mean it. You are likely to damage your liner, scrubbing that stuff.

What you need to do know, is get everything else up and running properly. You need to start swimming (it's not rougher than a concrete pool, I'm pretty sure). And you need to get your testing and pool care down to a comfortable routine.

Then, and only then, you'll be ready to tackle something that is rather complicated and confusing. There is no magic wand for this. But if you go to a pool store, I'm *sure* they'll be happy to sell you something, every time, while implying that THIS, finally, IS the magic wand you want.

I checked; you've done the pool chart. Thanks!

I'll try to get a pool log sheet done for you, tomorrow. Email me if I don't (I'm really swamped right now). Meanwhile test your fill water (pH, TA, CH) and post those levels. And, keep your pH in the 6.8 - 7.2 range and not higher.

[Wapak]

Ok, you wont have to tell me twice, I Hate Scrubbing!

Will look for the chart and continue testing.

When you get the chance, if you want to post some instructons on the removal of the scale that would be great. Just that I have a big pool party on july 4 planned so am hoping the grit may be on its way to going away by then.

Thanks for your help, i really appreciate it

[Wapak]

Hi Ben;

My test results this evening were
PH 6.8
Alkalinity: 170
Chlorine: Just a strong yellow now, it dropped from looking almost orange to the strongest yellow on the scale.

Pool is finally clear of the dead algae and debri that was in the bottom, and it actually is crystal clear in the shallow end. just the white stuff on the walls remains, and its still gritty. I noticed as me and the kids were swimming, the floor of the pool does not seem to have the buildup of this scale like the walls do.

also on the steps, I simply ran my hand over them some, and the scale build up on them was flaking off in chunks, unless now my steps are falling apart (wouldnt surprise me, thats my kinda of luck!)

And no, I am not scrubbing!

i didnt see a pool log sheet anywhere, unless I just dont know where to look, so just let me know.

Thanks for taking the time to help me!

[PoolDoc]

I have to make those individually, and haven't gotten yours done. But, with TA = 170, keep your pH low (6.8 - 7.0).

[Wapak]

If I do need to lower or increase ph, what product do you suggest using. i have some hth ph plus left, but will have to get something soon, so would like your opinion.

Thanks!

[PoolDoc]

Lower pH with muriatic acid -- BUT read the page linked in my signature, first!

Raise pH with borax -- 1/2 to 1 box of 20 Mule Team borax added slowly to the skimmer with the pump running.

[Wapak]

Hi Ben

Here is an update on my pool tests

Ph 7
Chlorine 3
TA still at 170

Just let me know, the water has been crystal clear, but that scale remains. just let me know, thanks!

[aylad]

Bumping this post back up....

[PoolDoc]

Hi Wapak;

Have you continued to hold the pH at 7.0? Is the pool remaining uncovered? If so, you should have seen a drop in TA by now. Once your TA gets below 100 ppm, you should begin seeing some scale removal or loosening.

Let me know, if you have not.

[Wapak]

Hello!

Its been a couple years since I posted here, but my pool has been doing fine since you last helped me, and thanks again!

However, this year, I have a different problem, but I think similiar in nature.

A week ago I opened my pool. The water was green, brown, dark. So I got everything up and running and checked my ph level first. It was really high, very dark purple. I started there. I didnt have any muratic acid, but I did have the hth ph minus granules, so I added about 48 ozs of it broadcasting over the pool. I then went around and brushed the sides some, but just let the filter run overnight.

The next day, I checked the ph again, it was down to 7.2. At that point, i started shocking by adding my bleach, I added bleach until it was reading a strong orange on my test kit (approx 10 gals). About two hours after beginning my shock, unfortunately, my pool pump motor stopped working (it ended up being the bearings).

The pool had to sit idle for three days while I waited on a motor. I did go out and lightly brush the sides, but nothing i could do other than that.

The motor arrived and I installed. It runs great-so i checked the water. My ph was back up to 7.8 and my chlorine level was down to 5.

So, I added more bleach to get the shock level back up. The next day (this past saturday) the water had cleared quite a bit. I could see the bottom, so I started vacuuming.

But, I now have large areas of an almost brown to tan to grey scale appearing all over my pool floor and walls. It does not completely brush off, i know some is coming off as a light cloud appears when i do vaccuum or brush over it.

My current readings are:

Chlorine (orange-off the chart of my test kit)
PH: 7.2
TA: 45 (that seems really low,but i checked it twice)

This seems like the same problem i had before, but it is now stained brown?? Is there any advice you can give me that may remove this without alot of continual brushing that doesnt seem to be doing a whole lot of good??

I have a picture I can post if you wish of it, but Im not sure how to put a photo on here, just let me know.

Any help would be so appreciated!!

[PoolDoc]

1. Email the picture to poolforum@gmail.com.

2. Next time your pump dies, remember that you can buy bleach and pour it in, even with the pump off.

3. Get a K2006, and do a FULL test of your pool chemistry (FC, CC, TA, CH *and* CYA). http://pool9.net/test/

4. Assuming your pool is filled from the same water supply as the toilets in your house, do a 'metals test' on your pool water: take the lid off a toilet tank, and see what color the interior of the tank is. Tell us what you see.

[Wapak]

Hello and thanks for responding!

Unfortunately, the best I could do is a HTH 6 way test kit, that is what I have also been using for the last couple years. I hope it is ok with those results, if absolutely necessary, i will hunt down a more in depth kit to post more results, Im hoping these numbers will do??

Right now:

Chlorine level 4
PH 6.8
Total Hardness: 550
Total Alkalinity 180
CYA: I used the entire bottle cya reagent that I had left, (35 drops) and still could not get the black dot to disappear.

My water is really hard as we have a well, this is what I do fill the pool from, so yes in my toilet tanks there is rust staining on the walls of the tanks.

But, I have had a little rust stain here and there, never alot, on the pool sometimes, this doesnt look anything like a rust stain i have had before.

I wanted to add too that this morning, after I had added more chlorine shock last night, it seemed to loosen alot of the darker patches of this stuff as I was brushing it.

I did email a picture, but you may want a better one, just let me know.

I think I answered as much as I could, but if not, please let me know if I can provide more info to you.

I have not added any bleach yet tonight, so if you do respond, let me know if you think I should keep shocking it. The pool water is still quite cloudy and hazy in the deep end.

Thank you again!

Rich

[PoolDoc]

Using more CYA reagent doesn't affect the reading: you mix a 50:50 solution of reagent + pool water, wait 2 minutes or so, and then see if the solution is 'cloudy' enough to make the drop disappear.

If it's NOT cloudy enough . . . you have zero stabilizer.

It's very, very unusual to have well water that is (a) hard [contains calcium] and (b) contains iron. Once you get the K2006, you'll need to test BOTH your pool water and your fill water. Try this link for the K2006, shipped BY Amazon (http://www.amazon.com/exec/obidos/ASIN/B004BGF7TI/scouscho-20/). Try it in the AM Tuesday and Wednesday. They may well have some then, and you'll get it faster from Amazon than from any of the other sellers on Amazon.

[PoolDoc]

Lemme add something else: you can't hurry the process of lowering alkalinity, except by aeration. You'll end up damaging your pool if you push the pH too low.

[BigDave]

... reagent + tap water, ...I'm pretty sure PoolDoc meant pool water.

[PoolDoc]

Oops.

[Wapak]

I was able to vacuum alot of dead algae out of my pool, a slimy mixture of that grit!

I pushed my return jets up so the water is breaking the surface.

My ph is holding at 6.8 but chlorine has dropped to 5.
Total alkalinity is reading again at 180, but since I am just starting the aeration I am hoping that will come down.

I have noticed there is an amount that is coming off and loosening with brushing and vacuuming.

I am going to reshock tonight and will let you know updates.

Thanks again!

[PoolDoc]

Total alkalinity is reading again at 180, but since I am just starting the aeration I am hoping that will come down.

That's the opposite of how what you'll see. As you aerate, your pH will rise with little or no apparent change in TA. The apparent change in TA will occur when you add your next dose of acid. Then, the pH will rise again.

You can simply maintain a pH of 6.8 to 7.0, while monitoring your TA. Once the TA reaches your target, hold the pH there, till the scale is gone.

But be careful. As your TA drops, it will take decreasing doses of acid to drop your pH.

[Wapak]

Oh ok, thanks for explaining that.

Do you have a suggestion on my target ta number I need to get down to? Or will I know that when this starts coming off in large amounts?

[PoolDoc]

What I expect is that you'll as you lower the TA, you'll find the scale gradually disappearing.

Just a caution: your calcium hardness may go UP, as you re-dissolve the scale. And, it may be necessary to either do a partial drain and refill OR do a lime softening process to lower the very high levels of calcium. But you'll be able to use your pool freely before that's necessary.

[Wapak]

Ok I tested again this morning, just my chlorine and ph.

Ph was high, 8.4

Chlorine was orange, I did shock last night.

Noticed tho that some very dark almost black spots on the deep end floor that wouldnt brush off yesterday are now gone this morning, finally the water especially in deep end is getting really clear.

I added a small dose of acid (less than a quart) since yesterday as soon as my chlorine went down, ph holds @ 6.8. Is that enough to add or would you advise a little more?

I plan on vacuuming, brushing andre-testing midday.

Also, my T A is turning from green to yellow instead of green to red. So I googled that and it looks like that is due to high chlorine. I will recheck my T A again at mid day.

[Wapak]

Just a quick update here at midday:

Chlorine is now a very dark yellow (was orange this morning)
ph is now at 7.8
I did not add anything now.
The T A test is still turning yellow so I cant provide a number on that yet.

I didnt have time to vacuum, but I did brush. Definitely some is coming off! As I brushed most of it seemed to settle at bottom, hard to tell how much.

I will vacuum this evening. I have been vacuuming so far just to waste, I haven't tried sending this stuff into my filter.

If you have any advice or if I should change what I am doing please just let me know.

I didnt do it now but this evening I will do a hardness test and provide that number.

All in all your instructions are working fantastically!. I will do my best to follow exact.

Thanks again

[PoolDoc]

+ Unless you still have live algae, or unless your CYA > 100 ppm, you don't need chlorine that is that high.

+ I don't remember, and haven't checked, your prior test results.

+ These videos apply, mostly, to the HTH 6-way => http://pool9.net/tk-guide/ http://pool9.net/tk-interfere/ The TA video, in the 2nd set, explains how to test TA when chlorine is high.

[Wapak]

Ok PoolDoc, here are my current test results I just took:

Chlorine. Close to 10just strong yellow now, no orange
T A: 160- I was able to read, it did not turn yellow as it did this morning. It also was at 180 yesterday when I started aerating.
PH: 7.5 (it was 8 earlier today)

I was going to add more acid to again lower ph-do you have any advice on amount? Do to this problem Im not exactly sure how much acid I should be adding??

Also, I have heavier build up along my deep end seams, its darker in color, I am just wondering if some of that is algae or just a thick pile of the scale? Some of it did go with brushing and vacuuming?

A pile of this stuff has been coming out my waste hose and filter basket holder-enough to fill a spoon! If you want me to send a picture got a great sample now I could get a pic of!!

[PoolDoc]

+ Use whatever doses you have before, but decrease them gradually. If you haven't been adding any particular amount, I'd start with 1/2 gallon of muriatic acid. If you find a dose takes you too low, reduce the dose.

+ Brush lightly those areas you think might be algae, but don't scrub.

+ Please send pictures to poolforum@gmail.com

[Watermom]

When you send the pics, include the thread number (16457) in your email.

[Wapak]

Still brushing off some, I can see its really brushing off in some spots where the coating was not as concentrated.

T A is most certainly coming down, its at 120-130 now.
ph holding at 6.8
Chlorine down to 1.-2.

Kids want to swim tomorrow, would you think its ok to let them in there for awhile? Didnt know if thats a good idea with the adjusting im doing?

Thanks again,

[PoolDoc]

Yes.

[PoolDoc]

Finally getting around to pictures:

https://lh3.googleusercontent.com/-aAD0WzrkVa8/U4yR3gbcZlI/AAAAAAAAHKE/3zdZPBor9Rw/s800/sand%2520algae%25201.jpg

https://lh5.googleusercontent.com/-9kaR1D-DKaM/U4yR4W7L9kI/AAAAAAAAHKQ/Cjt-Z-YXqzQ/s800/sand%2520algae%25202.jpg

https://lh4.googleusercontent.com/-ORiSvC_sXqs/U4yR3mpByDI/AAAAAAAAHKI/XlECn17EwTM/s800/pool.jpg


Color enhanced image:

https://lh3.googleusercontent.com/-4bWkbPHemnA/U4yR3jdMzHI/AAAAAAAAHKA/W-j9xH-Icr8/s800/pool-enh.jpg

[PoolDoc]

How's the battle with the grit going?

[Wapak]

Well, I am glad to report having a bunch of rowdy kids swimming in the pool seemed effective to pull up some of this stuff-there literally were piles of this grit in the corners, and on the floor which i was able to vacuum up the next morning. They also didnt even notice it as they were swimming, of course, its always on my mind, but they could have cared less!

There has been substantial amounts that have started to come up especially in the shallow end floor and the deep end floor.

I still have several areas on the walls, and on the seams around the deep end that just want to keep holding on.

I brush every night (i dont scrub), and every swipe does produce a cloud so I know its coming loose, just not as fast as I guess I want it to come off!

My TA has been difficult to get below 120. TA has held now for the last four days betw 120-140.

I have my returns turned up, and I use a power nozzle on my fill hose to spray over the surface of the pool water and create bubbles and fizz, but am thinking I may need to get a little more agressive on my aeration?? I saw where some have rigged up pvc pipes to do this-do you suggest that, or just stay the course with what I am doing?

My PH as come up several times (last read this morning was 7.5), but I just add a half gal of muratic acid and it drops by the next morning to 6.8.

Another question though, each season I use the Tri Chlor pucks in my chlorinator, but have not used any yet since opening the pool. Would you suggest that I go ahead and start putting the pucks in my chlorinator?

All in all, I would say I am winning with your advice, just have a feeling this is going to be a long war!

Thanks again PoolDoc

[PoolDoc]

The calcium carbonate bits are INCREASING both your TA and your CH, as they dissolve or break down. So it's not too surprising that you're finding your pool resists going below 120.

As the sand algae bits diminish, you should be able to lower the TA, and clean up the remnants.

[Wapak]

Hi Pooldoc,

my TA has finally dropped to 70-80ppm (this is the second day it has read that, was stuck at 120-130 for most of last week. I have been holding my PH between 7 and 6.8. it has generally taken 3/4 to one gallon of muratic acid, every other day to hold it there, the highest my ph has spiked was 7.2-7.5. my current chlorine is 1-2ppm.

The most progess i see on the scale coming off is usually right after a heavy swim day (kids jumping in and splashing all day). literally in my shallow seams and corners there will be little piles of it which are easy to vacuum.



I still brush every day, then vacuum the evening.

the lighter patches are diminishing for sure, specifically in my shallow end , but the real dark, thicker areas in my deep end dont seem to be budging much (these deep end patches have remained their same color, the darker brown, while the stuff that comes off is much lighter).

Just thought I would let you know an update. I havent used any pucks and will not!! I havent had to shock the pool, water has remained clear.

If you have any suggestions, or if you think I need to change something in my routine, please let me know.

I am a little concerned that the heavier stuff at the deep end does not seem to be 'chipping' off as quick.

Thank you again for your help and advice,

[PoolDoc]

No suggestions -- it sounds like you are doing exactly what you need, and getting the results you were seeking.

Just don't get impatient, and start scrubbing the liner, or lower the pH too far -- and I think it will be fine.

[Pappy]

The slower action in the deep end may be due to lower circulation and/or lower temperature. You might try hooking your vac head up and leaving it down in the deep end for an hour or 4 to stimulate circulation. See if you can tell a difference in the immediate area of the vac and other areas.

[Wapak]

Thank you Pappy, I will try placing the vac in the the deep end for a bit.