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howbout
03-28-2006, 10:38 AM
We have been having problems with our pool for a while and finally seemed to get them under control. But today I tested and it seems our pH is low! I read where you can add Borax to the skimmer to increase it - does anyone know if this is true??? Also, we have a pool cover and a pool heater. I live in FL and the days have been mid 70s lately falling into 60s at night. Though this past weekend it fell into the 40s at night...could my pool cover have an effect on the pH falling?

In other words...what should I do??? I am having friends over later this week and we'd like to swim but I want to make sure everything is balanced...:confused:

mwsmith2
03-28-2006, 10:48 AM
Yes, add borax to raise your pH. Not sure why your pH is low, you didn't really give much information, other than indicate you had a problem. How low is low? How big is your pool? How are you chlorinating? This will help us narrow down the cause of your low pH.

It's unlikely that a pool cover would impact your pH.

Michael

CarlD
03-28-2006, 11:55 AM
Bet you use Tri-Chlor pucks to chlorinate your pool. They are VERY acid and drive pH down.

Otherwise, MW Smith is right. I ONLY use 20 Mule Team Borax (from the grocery store) to raise my pH. I usually add 1/4 box at a time, wait 12-24 hours then test and add again as needed. However, if my pH is SERIOUSLY low (<6.9), I'll dump in a whole box, wait 6 hours, then test again and add if needed. BTW, my pool is 20k and vinyl lined.

Poconos
03-28-2006, 01:04 PM
I think part of the original question dealt with adding borax right in the skimmer. Yes. It will get sucked into the filter and then dissolve rapidly. Within minutes.
Al

howbout
03-28-2006, 01:20 PM
Yes, I did want to know about putting it in the skimmer - I actually just went out shopping and got some Borax.

The problems we had were low to no chlorine and the dreaded black algae but we got that under control. We used to have a service, but stopped it b/c the guy wasn't showing up and was saying he did. AND on a weekend we wanted to use the pool it was GREEN. So we figured if it's going to get green it may as well be our fault ;)

So right now I am in learning mode and VERY glad to have found this forum. I am going to add some Borax to the skimmer - the pH isn't HORRIBLY low but IS low and since I have kids who swim and their friends as well I always want the pool balanced perfectly.

You could say I've become obsessed with it I guess :D

Oh - forgot to say...it is an inground pool, about 15X30 but L shaped - it holds 11,620 gallons. And yes, we use the tabs to chlorinate, we were told they are the best way! Guess I have a lot to learn...what IS the best way to chlorinate if not with the tabs???

Watermom
03-28-2006, 05:15 PM
In my opinion, simply by using plain, unscented household laundry bleach. It is what many of us use. I use it exclusively and always have. In fact, I have never used any pucks at all in my pool nor any other chlorine source at all. Bleach works great, is cheap, readily available. The only downside for some people is carrying the jugs. But, that is not a big deal for me. In my pool, 24ft AG, I typically keep my stabilizer (cya) reading around 30-40 and add approximately 2-3 quarts (not jugs) of bleach per evening. It is easy for me. Takes me about 3-5 minutes per day.

Watermom

CarlD
03-29-2006, 11:08 AM
the pH isn't HORRIBLY low but IS low and since I have kids who swim and their friends as well I always want the pool balanced perfectly.

You could say I've become obsessed with it I guess :D

Oh - forgot to say...it is an inground pool, about 15X30 but L shaped - it holds 11,620 gallons. And yes, we use the tabs to chlorinate, we were told they are the best way! Guess I have a lot to learn...what IS the best way to chlorinate if not with the tabs???

The tabs are why your pH is low--they are super-acidic. Stop using them and switch to bleach and the pH should rise without doing anything else. Check your total alkalinity--it should be 90-125. If it's lower add baking soda--start with 1 lb, wait 12-24 hours, and test again. Keep going until it's in range. Since you have a vinyl pool, don't worry about it being too high unless you reach the 190-200 range--then you have to lower it, which is a pain, and explained elsewhere. But anything up to 180 in Total Alkalinity is not a problem--because you have a vinyl pool.

You also MUST get your CYA level measured--also called Cyanuric Acid, Stabilizer or Conditioner. That determines the minimum level of chlorine you need to maintain--and the max you can use to shock the water.

Since you've been using pucks, (I guessed right on that, didn't I? ) I'm also guessing your CYA is through the roof--100ppm or more. If so, you will either need to drain off a lot of water and replace it, or maintain very high chlorine levels--8-10ppm normally, and 20-25 to shock. Only practical way to lower CYA is by dilution--draining it off and replacing the water. (there is another way but it's very messy and unpleasant).

If you have CYA > 100ppm and are trying to maintain chlorine levels in the .5-3ppm range I can guaranteed you are headed for algae central. Pool guys usually mess this up and add tons of chems. Yours didn't--the clown didn't even show up! I suggest you pay him with Monopoly money--you'll stop pretending to pay him when he stops pretending he's working.

howbout
03-30-2006, 07:22 AM
Since you have a vinyl pool, don't worry about it being too high unless you reach the 190-200 range--then you have to lower it, which is a pain, and explained elsewhere. But anything up to 180 in Total Alkalinity is not a problem--because you have a vinyl pool.

Pool guys usually mess this up and add tons of chems. Yours didn't--the clown didn't even show up! I suggest you pay him with Monopoly money--you'll stop pretending to pay him when he stops pretending he's working.

Thanks for the info..but we do NOT have a vinyl pool, it's an inground. about 15X30 L shaped...and we fired the guy from the service last year (though that would have been a great idea with the money) :)

In any case, since I have added the Borax the levels have been perfect. I check every day...

Thanks again!

CarlD
03-30-2006, 09:35 AM
You are very welcome. But do yourself a favor and post your water test numbers--it's easier to see what's going on then, but at least, for now, it sounds like things are good.

howbout
03-30-2006, 11:25 AM
These are from March 18 from yes....the pool store analysis:eek: :
chlorine was 0 - I have obviously fixed that
ph was 7.8 - that too is now in the normal range according to my test kit
Acid Demand 1
Total Alkalinity 80 ppm
Calcium Hardness 325 ppm
Stabilizer 50 ppm

This is all they tested for. We had seen the water "foaming" and were told to next time ask for a TDS test. I am not sure we will be going back there next time so...the ranges they gave for the above were all fine for what we need (according to their analysis) except the pH was then high and of course there was no chlorine...

So any suggestions at this point? The pool is testing fine for both chlorine and pH now (my own test kit) but that is all I CAN test for. The water is crystal clear...

CarlD
03-30-2006, 02:36 PM
These are from March 18 from yes....the pool store analysis:eek: :
chlorine was 0 - I have obviously fixed that
ph was 7.8 - that too is now in the normal range according to my test kit
Acid Demand 1
Total Alkalinity 80 ppm
Calcium Hardness 325 ppm
Stabilizer 50 ppm

This is all they tested for. We had seen the water "foaming" and were told to next time ask for a TDS test. I am not sure we will be going back there next time so...the ranges they gave for the above were all fine for what we need (according to their analysis) except the pH was then high and of course there was no chlorine...

So any suggestions at this point? The pool is testing fine for both chlorine and pH now (my own test kit) but that is all I CAN test for. The water is crystal clear...

Acid Demand and TDS are useless tests just to impress you. Foaming could be the start of algae--shocking with bleach should fix it. If not, something else is causing it and Ben or one of the other moderators can help better than I can.

Total alkalinity is a bit low--the lowest end of acceptable--and if you lowered your pH it's gone even lower because T/A moves with pH. Add a pound of Arm&Hammer baking soda to fix it. I like it to be between 100 and 125. In a vinyl pool, you can go as high as 180 without worry.

CYA is at the maximum level that I like--50ppm. I would only chlorinate with bleach or liquid chlorine from now on. Your only other choice is Cal-Hypo--but your calcium is 325ppm, which is fine. Buy you don't necessarily want it too much higher, and Cal-Hypo will raise it. Stick to bleach.

So your CYA is high (but OK), your TA is low (probably too low)--and you have some foaming. You'll need to raise TA, shock your pool, then keep your regular chlorine level at a minimum of, say, 5ppm (I'll check that). and you should be OK.

howbout
03-31-2006, 07:06 AM
Well, that test was done back on the 18th. Like I said, since then we have treated the pool. At the time we did have algae. So those numbers really aren't anything you can work with NOW. The pool has been shocked,the pH brought up, etc. I think now from my tests and the way it looks everything is in shape. And don't forget it is NOT a vinyl pool, it is an inground pool!:D

CarlD
03-31-2006, 10:04 AM
Well, that test was done back on the 18th. Like I said, since then we have treated the pool. At the time we did have algae. So those numbers really aren't anything you can work with NOW. The pool has been shocked,the pH brought up, etc. I think now from my tests and the way it looks everything is in shape. And don't forget it is NOT a vinyl pool, it is an inground pool!:D

OK, but NOTHING you have done will lower your CYA--if you shocked with DI-Chlor or Tri-chlor it could go up. T/A will go up if you raise pH, and down if you lower it further.

Inground pools can be plaster, tile, concrete, gunite, fiberglass, or, yes, vinyl. Lots and LOTS of I/Gs have been vinyl for well over 35 years now (as a 15 year old kid I took care of a neighbor/friends's I/G--vinyl lined.)

So, ASSUMING you have concrete/plaster/tile, you absolutely must keep your T/A between 90 and 125--80 and 130 should be your trigger points to act. You must also keep your calcium hardness between 200 and 400 ppm--no lower or the water will leach calcium from the walls, no higher or you'll have scaling.

Keeping with that assumption, you have lost flexibility re: T/A and Calcium, but you gain it in pH. Where going below 6.9 is very dangerous in vinyl, you are much safer and could go down lower without fear (but I wouldn't because the water would be too acid). In an algae situation, you can safely raise chlorine levels FAR beyond the shock level for you CYA without fear of damaging or bleaching your liner--levels of 50 or 60ppm which would bleach a liner are not a problem. Also, muriatic acid poured into the water is less likely to damage the walls if it gets close to them. Muriatic will cause a vinyl liner to curl, soften and melt if too much actually contacts it--Muriatic Acid is best diluted and added to the deepest part of vinyl pools, slowly, so it can dissapate and not form a "slug".

New plaster/tile/concrete/gunite pools tend to go through a curing period. During this time your pH will keep rising and you'll be adding Muriatic all the time. This is normal.

Good luck with it.

VickieC24
04-03-2006, 12:17 PM
I think the clarification is that you have an inground pool that is NOT vinyl lined. (Maybe it's cement?) I have an inground pool with a vinyl liner.


Vickie


Well, that test was done back on the 18th. Like I said, since then we have treated the pool. At the time we did have algae. So those numbers really aren't anything you can work with NOW. The pool has been shocked,the pH brought up, etc. I think now from my tests and the way it looks everything is in shape. And don't forget it is NOT a vinyl pool, it is an inground pool!:D