How often do most of you add Muriatic Acid?

[FailedChemistry]

Hey everyone!

I use that mini test kit (Taylor K-1000) to test my water daily, and I'm always annoyed to find the pH hovering in the high 7.8 range.
Pool Calculator says to use 11oz Muriatic acid to get pH down to 7.5 — so i tend to add 16oz because that's easier for me to measure.

Typically, the next day my test will show a pH of 7.5 and i'll feel extremely accomplished. (Yay!)
But then the following day it's always right up at 7.8 again.
It seems to jump straight to 7.8 on the 3rd day and then hang out there for quite some time.

Is this weird?

I don't particularly enjoy adding the acid because the fumes scare me a little.
But it seems to me that if i want to keep my pool at 7.5, i'd have to add Muriatic every other day — which seems irritating and maybe excessive.
Or is that normal and i'm just a whiner?

Any help and/or advice would be greatly appreciated.

Latest tests:

FC	4
CC	.5
TA	100
CH	250
CYA	40
pH	7.8

 

[Richard320]

Every time I add water -- at least once a week.

 

[Jimrahbe]

FC,

What kind of cheese do you want...

7.8 is just fine... Let it sit there as long as possible.

My pool will often sit at 7.8 for several weeks.. it will sit at 7.5 for about 30 seconds...

Each pool is different of course.

Thanks,

Jim R.

 

[jblizzle]

Why do you need the pH at 7.5? Nothing likely wrong with 7.8, especially with your CH that is on the low side.

 

[Paul & Crystal]

I haven't put any in since March 10 when it was 8.2. I lowered to 7.5 and it has never moved. I heard that all pools are different though.

 

[FailedChemistry]

I don't need the pH to be 7.5, it's just the goal pool calculator defaults to, so i assumed 7.5 was the best.
And… CH 250 is low? I usually keep it around 260 for the same reason as above. Should i be keeping my CH higher?

Frankly, all my levels are based on the default goals in pool calculator. Is that dumb?

 

[jblizzle]

Make sure you are using PoolMath (link at the top) and not the old unsupported poolcalculator.com.

All the goals are ranges ... you should understand what they influence. What is your CSI ... that is important to look at for plaster/pebble pools. If it gets too low, you can damage the pool surface.

 

[Scoop]

Failed_Chemistry

It appears I have a pool similar to yours regarding the pH characteristics.

My pH usually bounces up to ~7.8 as well soon after a Muriatic Acid dosing.

Here's my MA dosings & elapsed time between dosings since 07-04-16 :

07-04-16 5 weeks
08-01-16 4 weeks
08-19-16 3 weeks
09-12-16 3.5 weeks
09-24-16 1.8 weeks
11-05-16 6 weeks
12-07-16 5 weeks
01-09-17 4.5 weeks
02-17-17 4.5 weeks
03-25-17 4.5 weeks
05-10-17 6.5 weeks
05-28-17 2.5 weeks


I usually dose MA for a target of 7.0-7.2 . That way, I can go a little longer between dosings. Also, the pH will only be at that level for ~1-2 days before it's back up at ~7.5 , then 7.8 .

I usually dose when the pH reading is 8.0 .

 

[Jason_Strobel]

usually weekly

 

[jblizzle]

Failed_Chemistry

It appears I have a pool similar to yours regarding the pH characteristics.

My pH usually bounces up to ~7.8 as well soon after a Muriatic Acid dosing.

Here's my MA dosings & elapsed time between dosings since 07-04-16 :

07-04-16 5 weeks
08-01-16 4 weeks
08-19-16 3 weeks
09-12-16 3.5 weeks
09-24-16 1.8 weeks
11-05-16 6 weeks
12-07-16 5 weeks
01-09-17 4.5 weeks
02-17-17 4.5 weeks
03-25-17 4.5 weeks
05-10-17 6.5 weeks
05-28-17 2.5 weeks


I usually dose MA for a target of 7.0-7.2 . That way, I can go a little longer between dosings. Also, the pH will only be at that level for ~1-2 days before it's back up at ~7.5 , then 7.8 .

I usually dose when the pH reading is 8.0 .

Remember, the pH will rise from 7.0 to 7.5 WAY faster than 7.5 to 8.0. I would not suggest lowering it that much unless your TA is very high and you are trying to lower it.

 

[Scoop]

I realize that. I lower it that way to also lower my TA as it tends to rise as well.

 

[FailedChemistry]

Make sure you are using PoolMath (link at the top) and not the old unsupported poolcalculator.com.

Ok. But the numbers are still the same.

My CSI is 0.3

I do realize the goals are ranges, but have no idea whether i should go higher or lower within that range, or why. So i just aim for the middle, or like i said previously, the default numbers pool math puts in.
I guess i'm not understanding what you're asking. Should i be keeping my CH higher than 260 or not?

And if so (or if not), how do i make that determination?
I don't really know what i'm doing other than what i've gotten from reading through this site. So all i can really trust is going by the suggested numbers here on the site.
What am i missing exactly? If i'm reading you correctly, you seem to be suggesting i take a more proactive role in determining the best levels for my own pool, but i don't have a clue how to even approach doing that.

Remember, the pH will rise from 7.0 to 7.5 WAY faster than 7.5 to 8.0.

And WHOAH. Where'd this nugget come from?
Does that mean pH will rise from 7.5 to 7.8 way faster than 7.8 to 8.0?
Why does this happen?

And seriously, thanks for taking the time. (That goes to you, and anyone who reads this) I truly appreciate it.
This stuff is just really confusing to me and i get frustrated.

 

[funandsun]

Certainly far more experienced folks already chiming in on this thread but from the chair of a guy who is pretty new to the management side of the water, I have arrived at the conclusion that all pools are different, some folks have pools that are happy as a clam at 7.5, others at 7.8.

My pool so far seems to be pretty happy around 7.6 and with that said my goal is to keep my water clean and glass clear... if I accomplish that and my tests are all passing, I am not going to fight 7.6 if that is where it seems to be happy.

I remember adding MA for the first time ever this year (I had always used pH down dry acid), I was far enough away and was careful pouring into my 5lb bucket but that did not stop the fumes from taking my breathe away. Dear goodness!

I hope your pool finds its happy place,

 

[pinguy]

First year I had my pool with fresh plaster && high TA - almost 1/2 gallon every day.

Now that the plaster has had a couple years to set and my TA lower, I'm at about 1/4 gallon per week.

 

[z33tec]

I haven't had to add any MA since buying my pool last summer. Not sure if that is weird or not. pH always seems to remain the same, within reasonable limits. Haven't had any issues yet about a year later.

 

[Perpetual summer]

Iam with z33tec, this will be first full summer. It has been opened since last week in April.
ph=7.6
ta=90
ch=280
ph hasn't budged yet, stays at 7.6. Ta stays at 90, and ch has stopped at 280, it was at 230.

 

[pinguy]

I haven't had to add any MA since buying my pool last summer. Not sure if that is weird or not. pH always seems to remain the same, within reasonable limits. Haven't had any issues yet about a year later.

Since you have vinyl and no SWG that's not so unusual. Every pool is a little different.

Plaster (especially fresh plaster), high TA, aeration (water feature or splashing), and SWG are the 4 things that lead to pH rise.

 

[Flbeachluvr]

Our pool is just a little over a year old and I add about 2 cups of MA every 3 days to get it to around 7.6. If I go longer than that I know it's well over 8 because the test results are a nice magenta color.

 

[Philo]

1/3 gal of 31% MA every 2 weeks. Goes from 8.0>>>>7.4.

 

[FattyLumpkin]

My pool has been at 7.4 - 7.5 for two years straight without ever needing to add acid. And it's saltwater, so the expectation is that the pH would rise more quickly than a traditionally-chlorinated pool. As everyone's said, seems as though every pool is different.