Converting to BBB

[chem geek]

As for the amount of Borax to add to raise pH, I now have this in my spreadsheet and can calculate that for you if I know your starting pH, TA, CYA (estimate) and pool size (in gallons) and your desired pH. In the meantime, the advice of adding a little and seeing the results is good.

As an example, let's say my pH is 7.3, TA is 100 and CYA is 30 and that I want a pH of 7.5. Then in a 10,000 gallon pool one has to add about 19 ounces of Borax. You would add proportionately more Borax in a larger pool or for a larger pH change.

Richard

[knarf#2]

Thanks- I'll check my levels and post them today, but just curious about the Borax/M. Acid method to adjust PH vs pool store bought PH-UP and PH down. Is it simply an economical issue or are the other benifits to using the borax/M. acid? I'm asking for two reasons 1) I have quite a bit of the pool store product left over and 2) I like the idea of having the specific amounts to add with the pool store PH adjustment products .

[chem geek]

Thanks- I'll check my levels and post them today, but just curious about the Borax/M. Acid method to adjust PH vs pool store bought PH-UP and PH down. Is it simply an economical issue or are the other benifits to using the borax/M. acid? I'm asking for two reasons 1) I have quite a bit of the pool store product left over and 2) I like the idea of having the specific amounts to add with the pool store PH adjustment products .

Yes, it's mostly an economics issue and the pH Up and Down products may be OK for you to use, depending on what they are, at least until you use them up. Read the labels and see if you can figure out if they are what I say below.

The pH Up is likely to be Sodium Carbonate which will not only increase your pH, but will also increase your Total Alkalinity (TA) (by more than what the pH would do alone). This is because you are adding "carbonate" to your pool -- making your pool more carbonated, just like a beverage! It is possible, though unlikely, that the pH Up is Sodium Hydroxide in which case this will be quite similar to Borax and will not increase TA (beyond that caused by the increase in pH).

The pH Down is likely to be Sodium Bisulfate which will add sulfates to your water. A little of this isn't terrible, there may even be some sulfates in your make-up water, but you don't want to overdo it. It has been reported elsewhere in this forum that Sodium Bisulfate can damage plaster surfaces, probably because it doesn't dissolve immediately so perhaps it would be better to put it into a large plastic bucket of water first (assuming the plastic is rated for acid) and then add it to the pool that way. In any event, you should add most chemicals to your pool over a return jet at the deep end to ensure the best mixing and dilution. The better way to lower pH is to use Muriatic Acid which is a liquid usually sold by pool stores as well (and some non-pool stores, etc.)

As for the amounts to add, the instructions on the bottles you have are approximate and only apply to pools with "typical" conditions of TA 100 and pH 7.5 as starting points. I can give you the same rule of thumb for Borax which is that 1 pound of 10 Mule Team Borax (which is Sodium Tetraborate Decahydrate) will raise the pH by 0.21 in a pool of 10,000 gallons. A larger pool needs more proportionately more Borax to achieve the same pH rise, etc. However, if you are starting at a different TA or pH, and you probably are, then the pH rise will be different which is why I said I could tell you what it would be if I had your numbers. Nevertheless, nearly everyone goes by these rule-of-thumb rules and generally add half the amount they need and then see what happens an hour later (then add some more).

Richard

[knarf#2]

I have a 15,000 AG and here are my test results from today. Probably should get the PH down a bit. How much M. Acid should I use? Anything else?
PH 7.8
TC 15
FC 15
TA 180
CYA 100

Thanks in advance

[Sully]

I have a 15,000 AG and here are my test results from today. Probably should get the PH down a bit. How much M. Acid should I use? Anything else?
PH 7.8
TC 15
FC 15
TA 180
CYA 100

Thanks in advance

Has your pool cleared? I wouldn't worry too much about ph, until your pool cleared up and stablized. But 1 cup of acid would bring it down a bit.

[knarf#2]

I'm definetely seeing improvements but it has not cleared as of yet.

Thanks

[chem geek]

I have a 15,000 AG and here are my test results from today. Probably should get the PH down a bit. How much M. Acid should I use? Anything else?
PH 7.8
TC 15
FC 15
TA 180
CYA 100

Thanks in advance

As Sully said, until your pool clears that should be your main focus. I didn't realize you had an algae problem and if you do, then you aren't at the shock levels according to Ben's Table which says you should maintain 25 ppm FC when your CYA is 100 (in fact, you may need even more, but at least get to 25). So first get your chlorine up and that should get you to clear faster.

Nevertheless, with your numbers, to get the pH down to 7.5 you need to add 27 fluid ounces (3 cups, 3 ounces) of Muriatic Acid. However, your TA and CYA are both quite high and at some point you should do a partial drain and refill which will lower TA and CYA (and FC, TC, CH). Again, you can do this after you pool clears.

Do you know why your TA is high? Is your refill water high in TA (you can test it if you don't know)? The high TA will cause your pool to outgas carbon dioxide at a more rapid rate and that makes the pH rise. Essentially, your pool is over-carbonated. After you solve your algae problem, you should first do the partial drain and refill to lower both TA and CYA. You should try and get your CYA down to no higher than 50. If after the partial drain and refill your TA is not down to 100, then follow Ben's Procedure for lowering TA. You can see from the following chart that you can't simultaneously maintain lower pH and high TA -- the pH will tend to rise as long as your pool is exposed to air (i.e. not covered). Increased aeration (splashing, wind, bubbles, etc.) make the pH go up faster.

Richard

[knarf#2]

When I returned from vacation to a green pool the first thing I did (being a newbie) was go to the pool store (in fact I went to 3 different stores and got 3 different opinions/advise). One of the stores told me that my TA was low so he sold us on some powder ( I can't remember what it was called or what was in it) and to be honest I can't even remember why he suggested this but being a newbie I just followed their advise blindly. Thats why my TA is high. By the way I don't know if this had any effect on TA but I also added A product called Bannish which is suppossed to be an algae destroyer and few days later I added a product called Green to Clean (more pool store advise). My pool went from dark green 2 1/2 weeks ago to light blueish today. After this very frustrating experience I decided to educate myself (thanks to you guys and this forum) and rid myself of relying on pool stores for my water management.

Thanks Again