Testing Inconstancies

[zraihusky]

Good afternoon! I am wondering if I could get some advice.

I am a little frustrated with how inconsistent my tests have been recently.
First pH, I was using a pH meter I got from Amazon. I had one before, but not sure where I got it from. However, the readings were not consistent with the Phenol Red tests. After reading the forums, I started relying on the Phenol Red tests and trying to calibrate the meter.
Now I am rethinking the vial tests, as I have usually used the chlorine drop test for my FC. However, I have noticed that the readings are not consistent with the vial R-0600 tests. Which is more accurate? How can I determine what is more accurate and when my products go bad?
I purchase the TF-Pro test every year to make sure the products are not expired. My test results are placed on PoolMath.

I'm trying to get my TA under control, as well as my CH (drained about 50% of the pool about 2 weeks ago).

 

[zraihusky]

PoolMath Logs

If that helps! I'm not the best at recording the chemical additions.

 

[kellyfair]

If you have the TF Pro, use the FAS-DPD for chlorine and the phenol red for PH.

 

[an1vrsy]

I'm trying to get my TA under control, as well as my CH (drained about 50% of the pool about 2 weeks ago).

Per your PoolMath Logs, TA 90 is just fine. Fortunately, you've turned on CSI. With your high CH 575, you will need to stay on top of your pH. Managing pH in the 7.4 - 7.6 range is way better than up around ph 8. When pH gets to 7.8 knock it down to 7.4. Play around with the CSI values on the Home page of PoolMath. Your daily test results are already entered there by default. Go in and modify or play around with pH values to see how CSI is affected. With a plaster pool, CSI is important.

edited: for clarity

 

[proavia]

Bring your TA down to 60-ish to slow the pH rise.
Don't use any baking soda or other products to raise the TA until it gets down below 50 - and then only to raise it to 70-ish.

Keep your CSI in the 0.00 to -0.30 (negative 0.30) range to minimize scaling in the SWG and calcium buildup at the water line.

If you are using unsoftened tap water for your autofill/makeup water, your CH will rise 200-300 ppm (or more) per year do to evaporation. Chances are your tap water has a CH of around 200+ and a TA of 110+.
Test your tap water (used in the pool) pH, TA and CH. Post the results here.

The best time to drain is in the cooler months - late fall thru early spring.

 

[zraihusky]

Bring your TA down to 60-ish to slow the pH rise.
Don't use any baking soda or other products to raise the TA until it gets down below 50 - and then only to raise it to 70-ish.

Keep your CSI in the 0.00 to -0.30 (negative 0.30) range to minimize scaling in the SWG and calcium buildup at the water line.

If you are using unsoftened tap water for your autofill/makeup water, your CH will rise 200-300 ppm (or more) per year do to evaporation. Chances are your tap water has a CH of around 200+ and a TA of 110+.
Test your tap water (used in the pool) pH, TA and CH. Post the results here.

The best time to drain is in the cooler months - late fall thru early spring.

Fill water:
TA: 140
FC: 1
CH: 125
pH: 8.2+ (over the test, pictures attached)

 

[Brian PacNW]

First pH, I was using a pH meter I got from Amazon. I had one before, but not sure where I got it from. However, the readings were not consistent with the Phenol Red tests. After reading the forums, I started relying on the Phenol Red tests and trying to calibrate the meter.

I also have a pH meter from Amazon. The calibration buffer powders are 100% necessary to get good readings. Then when immersing the probe into the water, you need to shake and wiggle it for a bit until the reading stabilizes; this takes me a good minute sometimes. Honestly the red phenol is faster for me.

 

[BDY]

You can’t calibrate off the phenol red..you need calibration solution (premixed) or powder (mix with distilled water) and calibrate at least monthly. Be sure to keep the tip stored moist/wet either in distilled water or KcL solution. It won’t be an instant read either - you have to let the meter sit until it atops moving.

Also the phenol red is not accurate if FC is over 10 so be careful of that too.

What meter do you have?

 

[BDY]

PS - the wiggling gets rid of air bubbles in the tip…an air bubble will through you off

The phenol red is easier per se but harder to read… a calibrated meter is more accurate and easy to read (especially if you run FC hot above 10) but needs some ongoing TLC to keep it accurate

 

[proavia]

Fill water:
TA: 140
FC: 1
CH: 125
pH: 8.2+ (over the test, pictures attached)

With TA of 140, it will take a bit of extra effort to keep TA in check. You may want to lower the pool water TA to 60.
Once at 60, let it rise to 80 on its own and then work it down to 60 again. Keeping TA at 60-ish will help reduce the pH rise.

Lower Total Alkalinity

A lower Total Alkalinity level can help a pool owner stabalize their pH increase. We'll explain how to lower TA with a little help from muriatic acid.

www.troublefreepool.com

Surprised your CH is only 125 - Not that 125 is a bad thing.
Did you happen to use a SpeedStir/SmartStir to do the CH test?
Did you continue to add drops until the color no longer changed and subtract the last drop?

 

[zraihusky]

With TA of 140, it will take a bit of extra effort to keep TA in check. You may want to lower the pool water TA to 60.
Once at 60, let it rise to 80 on its own and then work it down to 60 again. Keeping TA at 60-ish will help reduce the pH rise.

Lower Total Alkalinity

A lower Total Alkalinity level can help a pool owner stabalize their pH increase. We'll explain how to lower TA with a little help from muriatic acid.

www.troublefreepool.com

Awesome! Thank you!! I'm working on bringing it down. Question, I need to use the aerator in the summer to keep the pool temperature down. Doing so will increase the pH (as well as the fill water pH is high), so I need to keep adding acid all the time. Would I still use your advice with this information?

Surprised your CH is only 125 - Not that 125 is a bad thing.

I was surprised as well!

Did you happen to use a SpeedStir/SmartStir to do the CH test?

Yes.

Did you continue to add drops until the color no longer changed and subtract the last drop?

I did this as well. I never know if it will change more. I add another drop to see if it changes, if not I subtract it. Same with both TA and CH.

 

[zraihusky]

Can I toss in another issue I seem to be having? I see a lot of, what looks like, calcium flakes in the pool filters. That is from the SWG, yes? Will it affect the CH a lot? Should I be worried?
Here are pictures (along with a lot of husky fur! lol):

 

[proavia]

Awesome! Thank you!! I'm working on bringing it down. Question, I need to use the aerator in the summer to keep the pool temperature down. Doing so will increase the pH (as well as the fill water pH is high), so I need to keep adding acid all the time. Would I still use your advice with this information?

The aerator will increase the pH - but using it to aerate will help in the process to keep you TA low. Of course, the aerator also helps increase evaporation as well. So it possibly can be a double-edged sword. I haven't found my aerator helps cool the pool much at all and only use it occasionally.

Good to know you are taking the CH test to the end point instead of stopping to soon.

I see a lot of, what looks like, calcium flakes in the pool filters. That is from the SWG, yes? Will it affect the CH a lot? Should I be worried?

Gather some of those together and put a drop of acid on them. If it fizzes, it's calcium.
Yes - it's possible it's from the SWG. I don't believe it will affect the CH a lot - unless it dissolves into the pool water.
No need to be worried. In looking at your PoolMath logs, your TA and pH are a bit high, which is allowing your CSI to be high.
Attempt to keep CSI in the 0.00 to -0.30 (negative 0.30) range to minimize SWG scaling and the flakes you are seeing.
Play around with the TA and pH numbers in PoolMath to see what different TA and pH will do to the CSI.

 

[zraihusky]

The aerator will increase the pH - but using it to aerate will help in the process to keep you TA low. Of course, the aerator also helps increase evaporation as well. So it possibly can be a double-edged sword. I haven't found my aerator helps cool the pool much at all and only use it occasionally.

I keep the pool on all day. Living in Arizona, it is hard to keep the pool cool. As it runs at night with the aerator, it cools the pool over 4 degrees many nights. I use covers as well, but it's a pain to put them up and down every day due to the monsoons. We never know if it will be windy until I wake up in the morning with the covers blown over or away.

Good to know you are taking the CH test to the end point instead of stopping to soon.


Gather some of those together and put a drop of acid on them. If it fizzes, it's calcium.

Why didn't I think of that! Thank you!

Yes - it's possible it's from the SWG. I don't believe it will affect the CH a lot - unless it dissolves into the pool water.

Good to know! Thank you!

No need to be worried. In looking at your PoolMath logs, your TA and pH are a bit high, which is allowing your CSI to be high.

My pH is always high. I add what the app says, and even go back to make sure it is around 7. But the next day it is over 8.2 again. I am working on both the TA and CH currently. Though, I can't keep draining it too much during a month's time.

Attempt to keep CSI in the 0.00 to -0.30 (negative 0.30) range to minimize SWG scaling and the flakes you are seeing.
Play around with the TA and pH numbers in PoolMath to see what different TA and pH will do to the CSI.

Thank you! I am working toward that, and most of the time it is good. Except in the morning when the pH is high. And soon the TA will, hopefully, be normal.

 

[proavia]

Living in Arizona, it is hard to keep the pool cool.

You're preaching to the choir. I'm likely only 10 miles from you in Chandler. I think my pool hit 95° for a few days in July.

I use covers as well

Covers ON the water or OVER the water?

For the pH - let it rise to 8.0 and reduce it to 7.2. Aerate to raise back to 8.0 . This should have the biggest effect on TA. Once TA is down to 60, you may find a pH in the 7.6-7.8 range stays pretty stable and the CSI is in the range I listed above.

Try to aerate to reduce the pool temp only at night. Running the aerator to cool on a 115° day with a dew point in the 50's isn't going to have a huge affect on temps.

 

[zraihusky]

You're preaching to the choir. I'm likely only 10 miles from you in Chandler. I think my pool hit 95° for a few days in July.

If mine got to 95 I would not get in it! LOL It was 89 two days ago and I hated it!

Covers ON the water or OVER the water?

Over. I have four big umbrellas, three of which cover the water.

For the pH - let it rise to 8.0 and reduce it to 7.2. Aerate to raise back to 8.0 . This should have the biggest effect on TA. Once TA is down to 60, you may find a pH in the 7.6-7.8 range stays pretty stable and the CSI is in the range I listed above.

That is awesome! I will try that! I guess the only thing that would raise it would be the fill water pH and splashing. Dogs do the most damage. They remove more water than people, and splash much more than I do (though, I use the aerator all the time lol)

Try to aerate to reduce the pool temp only at night. Running the aerator to cool on a 115° day with a dew point in the 50's isn't going to have a huge affect on temps.

I'll do that. Well, probably after I get the TA down LOL

Don't get me wrong, I love my pups in the pool! Much easier to exercise them and myself with the temp outside. Plus, one of them lives for it! We have so much fun.

 

[proavia]

Yeah - just work on the TA and pH to get CSI in the 0.00 to -0.30 range.

Agreed - while we've had pups that didn't like the water at all (but would gladly ride on the raft), we had one dachshund that loved the water. He would jump right in and also dive for stuff. There were times when I thought it was his pool and he just let us use it. Never could train him to skim or do the chems though .

 

[zraihusky]

Yeah - just work on the TA and pH to get CSI in the 0.00 to -0.30 range.

Thank you for all the help! I think I'm getting it under control, except for this storm that messed up things. LOL

Agreed - while we've had pups that didn't like the water at all (but would gladly ride on the raft), we had one dachshund that loved the water. He would jump right in and also dive for stuff. There were times when I thought it was his pool and he just let us use it. Never could train him to skim or do the chems though .

LOL I know right... tell them to get a job, at least that's what I tell my "Riley".