How much borax to raise PH?

[denanbob]

Hi all! I'm baaaaaaaaccckkkkk.....LOL! We just uncovered after our first winter with a pool. At first I was scared because the bottom was green (but I could see all the way to the bottom which I knew was good). But after a good vacuuming to waste, the water looks GREAT! We added our DE, shocked, and then tested: Here is what we got:

TC-3
PH-6.8
ALK-280
CYA-60

So I used Muriatic Acid to bring down the ALK to 160 (I know I should go further), however the PH stayed at 6.8. I now need to raise the PH so how much BORAX should I use? After my initial shock treatment, I plan on using liquid bleach (used pucks last year because I already bought a huge thing before I found this forum). My pool is 15x30 AGP with 46 inches of water for a total of about 11,000 gallons. So how much Borax and how much liquid chlorine should I use on a daily basis?

Thanks soooooooooooo much!!!!

[JohnT]

You have a problem and it needs to be fixed quickly. Your pH was at 6.8 and you added acid. That means that it is now well below 6.8 because that's as low as your test kit can measure. It may have been below 6.8 before. You should start aerating your pool by whatever means you can, even if you can only point the eyeballs toward the surface. Get some borax in the water as soon as you can. You're probably going to run the store out. My ~20,000 gallon pool takes about a box of borax to move the pH up 0.1.

Acid does not lower alkalinity.

[denanbob]

You have a problem and it needs to be fixed quickly. Your pH was at 6.8 and you added acid. That means that it is now well below 6.8 because that's as low as your test kit can measure. It may have been below 6.8 before. You should start aerating your pool by whatever means you can, even if you can only point the eyeballs toward the surface. Get some borax in the water as soon as you can. You're probably going to run the store out. My ~20,000 gallon pool takes about a box of borax to move the pH up 0.1.

Acid does not lower alkalinity.

Acid doesn't lower alkalinity? I thought that's what everyone says to use to lower the alkalinity and then aerate to raise the PH??? Holy smokes am I confused now for sure. Anyway, I realize it's possible for the PH to drop below the 6.8 and I wouldn't know it since that's the lowest my test goes, but it is the same color as the 6.8 and it matches exactly, that's why I thought it was 6.8. If it was lighter than the 6.8, then I'd worry it was lower. But I will put Borax in as soon as I get home from work tonight to hopefully quickly raise the PH. I still don't know how much to add though. I guess I'll start with one box, but how long do I wait before I test to see how much it raised it? Does it take 1 hour or 8 hours? Does anyone know? I'm trying to figure out how much to add in what intervals. Thanks much!

[JohnT]

pH and alkalinity are directly connected. You add acid and the alkalinity drops, but the alkalinity will tend to pull the pH back up and the alkalinity goes back where it was. Aeration while the pH is low is what actually removes the alkalinity from the water and raises the pH.

[chem geek]

Ben's Lowering Your Alkalinity (http://www.poolforum.com/pf2/showthread.php?t=191) procedure step 3 says:

Use small doses of acid to lower your pH to just above the lowest value on your testkit -- or 6.6, whichever is higher. Do NOT lower the pH to whatever the lowest value on your kit is! In many cases, if you try to do so, you'll ACTUALLY end up with a much lower pH, which can damage your pool. Instead, make SURE that your pH is at least a little higher than the lowest pH value your kit shows. Also, do NOT try to lower your pH all at once; for all sorts of reasons, it's important to do it gradually!

I'm not putting this here to make you feel bad, but to make sure others reading this know to follow Ben's procedure exactly so that this problem can be avoided in the future. In short, do not target the lowest pH measurable on the pH test, but target one level higher. Since most test kits measure down to 6.8, that usually means using a pH target of 7.0 for this procedure.

Richard

[denanbob]

Ben's Lowering Your Alkalinity (http://www.poolforum.com/pf2/showthread.php?t=191) procedure step 3 says:

Use small doses of acid to lower your pH to just above the lowest value on your testkit -- or 6.6, whichever is higher. Do NOT lower the pH to whatever the lowest value on your kit is! In many cases, if you try to do so, you'll ACTUALLY end up with a much lower pH, which can damage your pool. Instead, make SURE that your pH is at least a little higher than the lowest pH value your kit shows. Also, do NOT try to lower your pH all at once; for all sorts of reasons, it's important to do it gradually!

I'm not putting this here to make you feel bad, but to make sure others reading this know to follow Ben's procedure exactly so that this problem can be avoided in the future. In short, do not target the lowest pH measurable on the pH test, but target one level higher. Since most test kits measure down to 6.8, that usually means using a pH target of 7.0 for this procedure.

Richard


Ok, let me change my question then. If my PH is 6.8 and my ALK is 300, what should I do in what order? For now I'm going to add BOROX right away, but I guess I should say what SHOULD have I done? I *thought* after lowering my ALK, I could aerate and add Borox to raise the PH since the temp is too cold to put the kids in it. I will aerate with raising the jets on one side and a fountain on the other end.

[JohnT]

Ok, let me change my question then. If my PH is 6.8 and my ALK is 300, what should I do in what order? For now I'm going to add BOROX right away, but I guess I should say what SHOULD have I done? I *thought* after lowering my ALK, I could aerate and add Borox to raise the PH since the temp is too cold to put the kids in it. I will aerate with raising the jets on one side and a fountain on the other end.

I would have started aerating right away. Wherever your pH was, it had been there a while, so a day or two longer wasn't going to be a big deal. Aerating at a pH of 6.8 will raise pH and lower alkalinity. As soon as your pH gets to 7.2, push it back down to 7.0 (one step above the lowest you can measure) and keep aerating. Stay at this until the alkalinity is where you want it, then let the pH climb back to the 7.4 to 7.6 range and see where you stand with alkalinity and how stable your pH becomes when you stop aerating.

If you have a fountain that goes on the return, that's a great way to go. If you're close to a pool store and can stop and get one that will go on your pool's return, I think it would be worth it.

[thilbert]

I agree with John here.

I had a very similar situation two seasons ago when I took over from the pool service company my then fiance used.

I had a TA of 400 and a pH of 6.8 or lower. I immediately bought a fountain for the return and installed it. Within a matter of hours, my pH had climbed to 7.0 and I was adding a little acid every 5 hours or so. I think it took me just shy of a weekend to bring my TA to 120 and pH to 7.6.

[chem geek]

Just to be technically correct, aerating raises the pH with no change in alkalinity. Adding acid lowers both pH and alkalinity. So the combination of the two ends up lowering alkalinity at a given pH. Carl explained this in this thread (http://www.poolforum.com/pf2/showthread.php?t=6746).

ACTIVITY .......... pH .... TA ... In your case (assuming 6.8 is the lowest measurement on the pH test kit)
==================

Acid ................. - ........ - ... Add enough acid to bring pH down to 7.0 (you were already below that so you skip this step)

Aeration ........... + ....... 0 ... Aerate until pH rises to 7.2
Acid ................. - ........ - ... Add enough acid to bring pH down from 7.2 to 7.0 (you may continue to aerate while you do this)
---------------------------------
Aeration & Acid .. 0 ....... - ... Continue this combination (cycling of the two above) until TA is at the target you want

then AFTER you have reached your target TA,

Aeration ........... + ....... 0 ... Aerate until the pH rises to your target pH (say, 7.5).

==================
Net of Above ..... 0 ........ -

So as the other posters said, when you are starting out with low pH but also have high TA, the best thing to do is to just aerate as that will raise the pH without raising alkalinity and gets you started in the above procedure that lowers alkalinity. So specifically in your case, assuming that 6.8 was the lowest measurement on your pH kit, you should have started aerating until you saw the pH rise to 7.0 and then keep aerating to let it rise to 7.2 and THEN add acid to bring it back down to 7.0 (after that, you bounce between 7.0 and 7.2 through aeration and acid addition -- all the while your TA drops). You never target the lowest pH measurement (6.8 on your kit) because you can never really know if it's truly at that pH or if it's lower. Hope that helps.

Richard

[denanbob]

You never target the lowest pH measurement (6.8 on your kit) because you can never really know if it's truly at that pH or if it's lower. Hope that helps.

Richard

Yes, that helped immensly. Thanks so much for taking the time to post all that. So no Borax at all then? When do you use Borax? LOL. Don't kill me...........I'm sorry for all the questions. I bought a fountain adapter for my aqualuminator today so I'm going to use that (I was going to add some Borax, but maybe I won't). I need to raise the PH before I use more acid to lower the alkalinity again, that I'm understanding. At the pool store, my numbers were 170 ALK and 7.0 PH. I will aerate to raise to 7.2, acid to lower to 7.0, and keep doing that until my ALK is in the target range. Right???

[chem geek]

After you get your TA where you want it (and after you are through with the TA lowering procedure), then if your pH gets too low at some point you can use Borax to raise it. However, unless you use an acidic source of chlorine (e.g. Trichlor) or a non-chlorine shock (e.g. potassium monopersulfate) or add CYA directly, then there shouldn't be anything in your pool making your pH go down.

The natural tendency for pool water is to go up in pH because it's been intentionally over-carbonated (like a tasty beverage!) and the outgassing of the excess carbon dioxide will tend to make the pH rise. Of course, when you stop the aeration, this tendency will be lessened, hopefully to the point where your pH will be stable. A lower TA will help this stability because carbon dioxide outgassing is faster at low pH, high TA, and with more aeration (so conversely, pH is more stable at higher pH, lower TA, and with less aeration).

Eventually, the slow outgassing of carbon dioxide and the small amount of acid you may add over time to maintain pH will result in a slow lowering of TA at which point you can increase it, but with properly adjusted water parameters, that day may never come. Every pool has a sweet spot or balance and after you've got your TA lowered, you'll learn what that is for your pool.

Richard

[tphaggerty]

I just went through something very similar. Opened pool to low PH (6.8 or lower), TA was OK, vinyl pool. I did BOTH, aerated and added borax. Why? My PH was low enough that I was worried that the vinyl liner might wrinkle as the pool warmed. So I started aerating (which did bring the PH up, but somewhat slowly) and added a large box of borax. After a few days, everything was fine.

The borax was an insurance policy, it made me feel better to get the PH up fairly quickly.

[Jeffski]

Sounds right to me. I think you only add Borax when your TA is correct and you need to raise your PH a little to get it correct. Great questions. I am still learning also.

[Ohm_Boy]

I like to think of the acid/aeration cycle as a 'ratchet' type of mechanism for adjusting TA.

You crank the TA down by reducing it and the PH with acid, then you 'reset the crank' by aerating to raise the PH back up leaving the TA where it is.

Repeat as necessary.

...but I tend to be a simple type of guy. :)

[denanbob]

I know everyone says if I follow the "how to lower your alkalinity" thread exactly, it WILL work. HOWEVER, mine will not budge below 160. It went from 280 to 160 using this method, but no matter how much muriatic acid I add now, it won't budge. I'm aerating with a fountain that sprays out of my return and really seems to be bubbling and rippling the water. Also, we had a good rain last night too. Still not moving down. My PH went up from 6.8 to 7.5 with Borax. It went back down to 7.2 with the acid, and now back up to 7.5 with the aeration. I will add more acid to lower it again (no lower than 7.0 I know), and keep aerating I guess. I still don't understand why the ALK won't budge any further than the initial 120 drop from 280. If the water wasn't 64 degrees, I'd let my kids get in there to further aerate.

[JohnT]

I wouldn't be worried about it at 160. I lived with mine at 200-ish for some time before winter rain dilution dropped it. As long as you don't have high calcium hardness and you aren't experiencing cloudy water, leave it be. I always pushed my pH down to 7.0 whenever I had to add acid, and it seemed I'd gain a little every time, but I didn't work at it.

[Ohm_Boy]

Ben always said that pools find a value that they 'like', and you're best bet is to learn what your pool likes and manage around that.
160 ain't too bad.

[denanbob]

Ok, these were my numbers from this morning using the HTH 6-way test kit from WalMart:

TC - 4
PH - 7.4
ALK - 140 (it actually came down 20 more and now I'm DONE with it! LOL)
TH - didn't work

I know we have hard water (from a well, and no softener). When I filled pool water to the appropriate line and added 5 drops of hardness indicator, the water turned a light yellowish/tan instead of red like it said. Then I was supposed to add the titrant drop by drop until the "red" water turned blue. I kept adding (just to see what color my yellow would turn) and nothing changed. If anything it looked a little more clear colored. Does this mean my hardness is waaaaaaaaaaaaay up there, or that my chemicals need replaced maybe? I bought the kit last year in July. Not sure how long they are "good" for. Any ideas? Last year my hardness was 480 (yikes) but we have a vinyl pool and no problems with cloudy water so I didn't mess with it.

Dena
15x30 Esther Williams AGP 10,000ish gallons