Acid Demand Higher After Adding Borates - Normal?

[shmuby]

Hi All,

Prior to adding 50ppm of borates to my pool (I used boric acid from Duda Diesel), I had very high pH. This was probably due to my SWG and spillover spa. However, the acid demand was always quite low. Sometimes a single drop would take that sample (K-2006) from a fairly dark red back to orange.

After adding the borates, it seems that sometimes it takes 2 or 3 drops to do what 1 would previously do. Is this normal? Does this mean that while the borates do indeed stabilize the pH bounce, it will take more acid to drop the pH when I do add it?

I was adding about 1-2 cups/week before. I haven't really figured out how much I'll need now. I used to rely on the acid demand test a good bit because I have such a hard time telling the difference between 7.8 and 8.0 on the scale. Basically I would toss in a cup or so of acid when it took 2 drops to get back down in the 7.4-7.6 range. I feel like I'm flying a bit blind now.

Thanks,
Shmuby

 

[Sunnydaze]

Hi All,

Prior to adding 50ppm of borates to my pool (I used boric acid from Duda Diesel), I had very high pH. This was probably due to my SWG and spillover spa. However, the acid demand was always quite low. Sometimes a single drop would take that sample (K-2006) from a fairly dark red back to orange.

After adding the borates, it seems that sometimes it takes 2 or 3 drops to do what 1 would previously do. Is this normal? Does this mean that while the borates do indeed stabilize the pH bounce, it will take more acid to drop the pH when I do add it?

I was adding about 1-2 cups/week before. I haven't really figured out how much I'll need now. I used to rely on the acid demand test a good bit because I have such a hard time telling the difference between 7.8 and 8.0 on the scale. Basically I would toss in a cup or so of acid when it took 2 drops to get back down in the 7.4-7.6 range. I feel like I'm flying a bit blind now.

Thanks,
Shmuby

My understanding is that because borates buffer ph well, you don't add acid as often but when you eventually need to decrease ph, it takes the same amount you would have used accumulatively. Meaning you use the same amount of acid, you just dont add it as often.

 

[YippeeSkippy]

My understanding is that once you add borates it becomes more difficult to adjust things. That's why we only recommend you adding borates if your settings are stable and you're not having to tweak them often.

Maddie

 

[Rancho Cost-a-Lotta]

With borates, more muriatic acid is needed to adjust pH the same amount as without. pH rise slows down proportionately, so you use about the same amount of MA. Use Pool Math to calculate the amount of MA needed. Make sure you record the current borate level. You can also download the Pool Math app.

 

[shmuby]

Thanks for your replies - this makes sense and matches what I've seen. I should be ok here if I can figure out a better way to differentiate between 7.8 and 8.0 pH. My usual plan is to allow the pH to float up to 8, and then knock it back down to 7.6 with muratic acid. This used to be a once/week cycle or so.

I had my numbers as steady as I could before adding the borates. My pH was 7.5, Total Alkalinity was 60-70.