Proper PH for closing

[laren]

What is the proper PH reading for my pool upon closing? At the pool store they told me it should be 8.0 or above. Do I just bring the chlorine up to shock level or twice that amount for closing?

Thank you,
Laurie

 

[duraleigh]

Hi, Laurie,

I don't close my pool but I can think of no reason to raise the pH. 7.2-7.6 (normal Summer range) is where I think it should be. Did they offer you an explanation? Did it make sense? At this point, it doesn't to me.

 

[laren]

Hi Dave,

They didn't offer an explanation for the high PH. It's been a rough summer...I got rid of the algae then it came back got rid of it again only to have it return. So I went to the pool store last week and she tested my water, keep in mind I only used bleach from the time I joined this forum (with the exception of a grandular shock, once about a week and a half ago), here are her readings of my pool water and what she sold me to rectify

TDS 700
CYA 100
CL 5
TC 5
PH 8.2
TA 98
adj. TA 63
CH 145
CYA 100

She sold me 8 lbs. of baking soda and 3 lbs. of calcium which I put in the pool. My readings the same day I brought in my water sample to the store were totally different from hers (my readings before the pool store)

CYA 40
PH 7.5
TA 140
CL 21.5
CC 0

Now I really couldn't understand how my CYA got to 100 using bleach and I think my reading was correct at around 40 but I was desperate the algae had returned and I couldn't understand why unless my readings were wrong. So hear it is the end of summer and I'm still confused and terrified the algae will return.

When I told her my chlorine was at 21.5 ppm she told me that I couldn't possibly know tbat, you can only test to 5 ppm, even when I explained my method of testing (my chlorine was high because I had shocked to kill mustard algae a few days earlier)

I questioned her about her readings and the ingredients she was selling me for the pool, but she only got angry and said that I was being too technical. Against my better judgment I added the baking soda and calcium. I have no algae at the moment and I just want to close the pool, any suggestions

Thank you,
Laurie

 

[duraleigh]

Laurie,

Glad you posted back some detail. You have an uninformed pool store and you will not have much to gain returning there other than to buy supplies you can get nowhere else.

First, let's review the algae issue. Algae will not grow in your pool if you keep adequate chlorine in it....it's really that simple. If your algae returned, it's because the chlorine slipped below an acceptable level allowing it to get a foothold. Once it does, it's a little tougher to get rid of than to prevent but the answer will always be CHLORINE.

I trust your readings over her's. You had no need for either baking soda or calcium but no harm done. It seems you may not be testing your pool frequently enough (at least for now) Keep a daily eye on chlorine so it doesn't ever slip below 3-5ppm....that should solve your algae returning.

Next, post back some current info on pH and Alk. You may need to work on that a little but not much. Check that around twice a week (or a little more) to make sure it's consistent and steady. No need to post CYA unless you doubt your earlier test results and calcium is irrelavant in your pool if it's vinyl lined. Test and post it (CH) if it's a masonry pool.

 

[JasonLion]

I second what duraleigh said. If you are using a drop based test kit then trust you own numbers over the pool store numbers.

 

[laren]

I will get those reading to you as soon as it stops raining. I tested my chlorine twice a day and I never let it slip below 7 ppm. I'm pretty sure that it is mustard algae that I'm dealing with and maybe I didn't hold the high chlorine level long enough. Next year I want to put something in the pool when I open it to make sure I never have algae again, any suggestions as to what would be the best maintenance algaecide

I went out to find polyquat 60 today and all I could find was algaecide 40 having the same ingredients, will this be sufficient?

Thanks,
Laurie

 

[JasonLion]

Often the 40% algecide is the same as the 60% algecide except that you need more of it, which generally ends up being more expensive. If you check the ingredients list, as you did, and it is the same then you can use it if you can't find the 60% strength.

If your CYA is 40 then FC of 7 should have been more than enough to keep the algae away. If, on the other hand, your CYA is 100 then FC of 7 would have been marginal and it would have been easy to get algae. What kind of test kit do you have and how old is it? It is common enough for pool stores to get some of the test numbers wrong, but it is fairly unusual for them to get everything completely wrong.

 

[laren]

I bought my test kit from this site in late July or early August from Dave.

I can't see how my cya level could be 100. Just after I started using bleach I had my water tested at the pool store and they told me it was 80. Because the cya was so high we emptied at least 1/3 of the pool water.

Last week my test put me around 40 cya. A short time ago we used a granular shock product a one time occurance, certainly that didn't raise my cya by that much

Laurie

 

[chem geek]

If the "granular shock" was Dichlor, then for every 1 ppm FC added, it also adds 0.9 ppm to CYA. So if you shocked to 15 or 20 ppm FC, then you added about that much to CYA. "Granular shock" can also mean Cal-Hypo which doesn't add to CYA (though it increases Calcium Hardness, CH).

 

[JasonLion]

Alright, your test is reliable then.

Another possibility is that it isn't really algae. Have you felt it, does it feel slimy? Does it grow on the walls, or settle on the floor of the pool, or color the water? Some kinds of dust and pollen can look like mustard algae. Another test is chlorine loss. Mustard algae will consume chlorine more quickly that usual. Have you needed to add extra chlorine (other then when you were shocking)? Have you had any CC?

 

[laren]

I just did a test here are the results

FC 17.5
cc 0
TA 225
PH 7.8
cya 50

The skimmer sock is still green but the water is clear. I'm not sure if it's algae, all I can tell you is it settles on the floor of the pool but brushes up easily, like a fine dust. I posted pictures this summer of how it looks when it gets bad the actual colour of the pool looks green and you can't see the bottom.

Thanks,
Laurie

 

[duraleigh]

Laurie,

Algae is the answer in almost every case.....in your's, I'm beginning to think not. The tip to me is when you said your filter is green. Any dead filtered algae is usually dirty brown or gray and has lost the majority of it's green characteristic.

I'm beginning to think you've got some airborne type of pollutant like pollen. I rarely, if ever, am willing to suggest anything other than algae but your Chlorine history and the contents of your filter suggest another issue.

Do you have any of those skimmer socks? That would be almost a dead giveaway.

Double check that Alk test....that's not consistent with your previous results.

 

[laren]

Dave my TA is correct, remember the pool store had me add 8 lbs. of baking soda. I have a skimmer sock and that's where the green is most noticeable at the moment (the pool looks clear). If you look at my pictures under Algae, green cloudy water, that's what I have been dealing with all summer.

Thanks,
Laurie

 

[duraleigh]

Sorry, I forgot about the baking soda. I suggest you go ahead and reduce that Alk....your pH is probably gonna start to rise. Are you familiar with reducing Alk (acid,aeration,acid,aeration,.etc) If not, post back and we'll walk you thru it. It won't cost any money but is kind of a slow process.

I'll go revisit the pics to see if that sheds any light.

 

[laren]

Thanks Dave, All summer I've been trying to lower my TA, I finally got it down to 140 from way over 200 and the store gave me baking soda, again. What I did is lower my PH to 7.0 then aerate, by the way is there any point in adding PH down when it's raining? You're right it's a very slow process and there's no way I can get it back down before I close the pool, will this be okay?

Thanks,
Laurie

 

[laren]

Alright, your test is reliable then.

Another possibility is that it isn't really algae. Have you felt it, does it feel slimy? Does it grow on the walls, or settle on the floor of the pool, or color the water? Some kinds of dust and pollen can look like mustard algae. Another test is chlorine loss. Mustard algae will consume chlorine more quickly that usual. Have you needed to add extra chlorine (other then when you were shocking)? Have you had any CC?

Hi Jason, The only place I was able to feel the algae was in the skimmer sock, and no it doesn't feel slimy but it's bright green. The dust is more on the floor of the pool and eventually turns the water green. When I test for cc's it's always 0.

Thanks,
Laurie

 

[JasonLion]

It would be best if you stop listening to advice from that store. They have told you several things wrong at this point.

I don't think you need to get the TA down before you close. Work on it when you can and stop when it is time to close.

Adding acid before or during rain is great. The rain will aerate the water.

More and more that sounds like some kind of pollen.

 

[waste]

Laurie, having looked up a number of your old posts, I've discovered that you have an AG pool - therefore liner. (Please give a look at the sticky I authored in the "POOL SCHOOL" section and think about setting up a signature with your pool's specs )

Your original question was about the high pH when closing, I followed how and why the original shifted focus and have enjoyed following this thread. I do want to give my take on a higher pH for closing a liner pool. In the end, it depends on whether rain and snow will end up mixing with the pool water [this depends on whether your cover allows water through or if you even use a cover] - if the precipitation will mix with the pool water, I believe you will be better off closing with a high pH. The reasoning behind this is that at the very least the precip. is 7.0 and will dilute the pH of the water, if you live where the precip. is acidic it will draw the pH down even faster - liner pools should be kept with a minimum of 7.0, I shudder to think of the damage that could be done to a liner that sits unchecked for months with a low pH- a lot of unnecessary wear on the liner can be prevented by anticipating the effect of neutral/ acid precip. and having the pH on the higher side when closing.

I know that in the second post on this thread, Dave said to leave the pH at regular, Summer, levels and that he doesn't cover his pool - all I can say is that Dave has admitted to 'not being too smart' in the past -- in fact I'm positive he never bought one of Duraligh's great kits , HE probably uses test strips (most likely expired ones :lol: ) {sorry Dave, you know I'm just " " -ing fun}

As is typical, I forgot about 1 thing while trying to be funny :grrrr: What you MAY have going on is what I've termed "Matt's Mud" or "4X4 Algae". Matt4x4 posted about it on PF last summer. This seems to be a form of persistent algae that has the look of some of what you describe. I'll either pm him or x-link the threads from there - but it won't be tonight I've gotta go

 

[laren]

Laurie, having looked up a number of your old posts, I've discovered that you have an AG pool - therefore liner. (Please give a look at the sticky I authored in the "POOL SCHOOL" section and think about setting up a signature with your pool's specs )

Your original question was about the high pH when closing, I followed how and why the original shifted focus and have enjoyed following this thread. I do want to give my take on a higher pH for closing a liner pool. In the end, it depends on whether rain and snow will end up mixing with the pool water [this depends on whether your cover allows water through or if you even use a cover] - if the precipitation will mix with the pool water, I believe you will be better off closing with a high pH. The reasoning behind this is that at the very least the precip. is 7.0 and will dilute the pH of the water, if you live where the precip. is acidic it will draw the pH down even faster - liner pools should be kept with a minimum of 7.0, I shudder to think of the damage that could be done to a liner that sits unchecked for months with a low pH- a lot of unnecessary wear on the liner can be prevented by anticipating the effect of neutral/ acid precip. and having the pH on the higher side when closing.

I know that in the second post on this thread, Dave said to leave the pH at regular, Summer, levels and that he doesn't cover his pool - all I can say is that Dave has admitted to 'not being too smart' in the past -- in fact I'm positive he never bought one of Duraligh's great kits , HE probably uses test strips (most likely expired ones ) {sorry Dave, you know I'm just " " -ing fun}

As is typical, I forgot about 1 thing while trying to be funny What you MAY have going on is what I've termed "Matt's Mud" or "4X4 Algae". Matt4x4 posted about it on PF last summer. This seems to be a form of persistent algae that has the look of some of what you describe. I'll either pm him or x-link the threads from there - but it won't be tonight I've gotta go

I don't believe our winter cover allows much water into the pool. It usually has a lot of water on top of the cover which freezes in the colder months.

What do you recommend for a ph level upon closing?

Also, I was reading a post from (onemom) under Algae Treatment and Prevention and her situation sounds identical to mine!

Thank you,
Laurie

 

[waste]

Laurie, if the cover will keep the precip. separate from the pool water, there is no reason to change it from the normal 7.2 - 7.8. If you had a cover that would allow the water from the sky and your pool water to mix, and you had inches of acidic rain expected, I would take the pH to ~8

Thank You for your new sig.!!!!

(I'll try to get Matt's attention, he's the one who brought the ~new algae to my attention and could probably tell you better than I how to deal with it - though I've read of something that may work...)