Differing Chemical Level Recommendations

[Dabby]

I have a new plaster pool. It's been full about 3 weeks. It is 24,300 gallons and has a SWG.

My question is about the differing chemical recommendations I am running into.

ProLogic Controller Instructions: Pentair Test Kit TFP
FC 1-3 FC 1-3 FC 3-5
TA 80-120 TA 80-120 TA 60-80
CYA 60-80 CYA 30-50 CYA 70-80
CH 200-400 CH 200-400 CH 250-350

Most everything is close except TFP recommends higher FC and lower TA. There are 3 different levels for CYA. The Pentair kit (came with the pool - waiting on my TFP kit) instruction booklet says FC should be 1-3, but the test block says ideal is 1-1.5.

Right now I have crystal clear water and no problems. I do have to add acid fairly frequently to keep TA and PH down. I would just like to know what levels I should be shooting for.

Thanks

 

[Richard320]

I have a new plaster pool. It's been full about 3 weeks. It is 24,300 gallons and has a SWG.

My question is about the differing chemical recommendations I am running into.

ProLogic Controller Instructions: Pentair Test Kit TFP
FC 1-3 FC 1-3 FC 3-5
TA 80-120 TA 80-120 TA 60-80
CYA 60-80 CYA 30-50 CYA 70-80
CH 200-400 CH 200-400 CH 250-350

Most everything is close except TFP recommends higher FC and lower TA. There are 3 different levels for CYA. The Pentair kit (came with the pool - waiting on my TFP kit) instruction booklet says FC should be 1-3, but the test block says ideal is 1-1.5.

Right now I have crystal clear water and no problems. I do have to add acid fairly frequently to keep TA and PH down. I would just like to know what levels I should be shooting for.

Thanks

The FC is dependent upon the CYA level. Once you have tested the CYA and know where it is, maintain it using the TFP recommendations for SWG on Pool Calculator. It's only a little higher than the others recommend, but it's cheap cheap insurance.

TA is sorta by trial and error. I sort of obsessed on driving TA down by acid and aeration for a while. Two days later, it would be climbing again. Seems like no matter what I do, TA on my pool is either 80 or 90, consistently. Each pool has its own personality, as it were. If you get everything settled and pH keeps climbing (it will with a SWG anyway) maybe you need to lower TA. If things hold steady for you at 120 - leave it alone. Just pay attention to the CSI. You have a nice smooth finish - don't let it start scaling!

 

[Dabby]

My TA keeps climbing. I add acid to bring it down to around 100 and then a few days later it's back up to 120-130. Is it normal to have to add a gallon of acid every week?

Should I bring it down to around 80 and see how long it takes to get back to 120 or should I try to keep it more even?

Or should I just add a little every few days to keep it at 120?

 

[Dabby]

Ok, I thought I would provide a little more information. Right now, according to my test kit, the pH is 8.2, the TA is 130 and Chlorine is about 2 (between the 1.5 and 3 levels on the test block).

This is what the readings are every week when I test (I am testing chlorine more often and it is always the same). According to the charts in the kit, I would add 1 1/4 pint to bring the pH down to 7.6, but 1 1/4 gallon to bring the TA down to 100. So, which should I add, the pint or the gallon?

Thanks again.

 

[dmanb2b]

Welcome to TFP Don't worry about TA for right now, unless it drops below 60. PH is your main concern and you want to keep that below 7.8 at all times. It is normal in a new plaster pool for PH to rise rapidly, especially if you also have water features. Unfortunately, you will require frequent acid additions over the next year or so. It gets easier as the plaster cures...from pool school

Gunite/Shotcrete/Plaster/Quartz/Pebble

Gunite pools are available in a limitless variety of fully custom sizes and shapes. They also offer many options for enhancing the plaster surface, including coloring, and adding small quartz crystals, glass beads, or pebbles of various sizes. They take the longest, and are the most expensive, to install, and they require the most maintenance.

Caring for the plaster properly during the first month is very important and is more work than most people expect. After the first month, it gets easier, though maintenance is still more work than the other kinds of pools. If properly cared for, the plaster surface can last a very long time, especially if quartz or pebbles are added to the plaster. When the plaster does wear out you can re-plaster, though that can be expensive.

Darker colored plaster often has a mottled appearance that many people don't like. Adding quartz crystals to the plaster can look wonderful, and increases the lifetime of the plaster. Adding pebbles to the plaster can look amazing, and extends the life of the plaster even more than quartz crystals. The larger pebbles can sometimes cause the surface to be uncomfortable to walk on. Adding quartz, glass, or pebbles to the plaster is often expensive.

 

[Lana537]

Ok, I thought I would provide a little more information. Right now, according to my test kit, the pH is 8.2, the TA is 130 and Chlorine is about 2 (between the 1.5 and 3 levels on the test block).

This is what the readings are every week when I test (I am testing chlorine more often and it is always the same). According to the charts in the kit, I would add 1 1/4 pint to bring the pH down to 7.6, but 1 1/4 gallon to bring the TA down to 100. So, which should I add, the pint or the gallon?

Thanks again.

Hi Dabby~~

Has your TFP-100 test kit arrived yet, or are the pH readings you are posting coming from the Pentair test kit you have? If you are still waiting on the good test kit, what type of pH test is in the kit you now have? I'm getting at how accurate your pH readings are---is it a phenol red drop reagent test or some sort of strip test?

Your main concern should be keeping that pH down, but you need to have a trustworthy test. Use the pool calculator to figure out how much MA to add. Your chlorine generator and your new plaster will keep that pH rising, and you'll have to keep swatting it with the MA.

Lana

 

[Melt In The Sun]

Have you added salt already?

 

[Dabby]

For the easy question first, yes the salt has been added and SWG indicates 2900ppm.

The TFP-100 has not arrived yet. The pH test I'm using is a drop test, not a strip.

I definitely don't have to worry about the TA dropping too low, it keeps climbing. When I started testing, TA was consistently 130ppm and pH was 8.2. I was adding the greater of the two amounts of acid, either to lower the TA to 120, or lower the pH to 7.6. Then I read the TA should be lower, 80-100, so I put in a gallon of acid. I also thought this might keep the pH from climbing so rapidly. That lowered the TA to 100 and the pH was 7.6. That was last week. Like I said earlier, today the pH was back up to 8.2 and the TA was 130.

So, from what you all are saying, it IS normal for a new pool to require frequent additions of acid, correct? Should I be testing the pH more than once a week? Should I add a lot of acid at a time to keep the TA down, which will also take care of the pH, or should I make more frequent, smaller additions of acid to keep the pH down and not worry about the TA? If I let the TA rise, at what point would it be TOO high, or does it even matter? What would you say an average amount of acid per week would be?

As far as the chlorine, my test block only shows up to 3.0, so I will have to wait for the TFP-100 to adjust that.

 

[PaulR]

So, from what you all are saying, it IS normal for a new pool to require frequent additions of acid, correct? Should I be testing the pH more than once a week? Should I add a lot of acid at a time to keep the TA down, which will also take care of the pH, or should I make more frequent, smaller additions of acid to keep the pH down and not worry about the TA? If I let the TA rise, at what point would it be TOO high, or does it even matter? What would you say an average amount of acid per week would be?

A brand new plaster pool will have rapidly rising pH at first; the good news is this slows down over time, the less-good news is it can take a year to really settle down. A SWG will also tend to contribute to rising pH. High TA will also tend to contribute to rising pH.

Pool School doesn't really stress this, but swimming in the pool will tend to contribute to rising pH. I've found that looking at the pool sideways will tend to contribute to rising pH. I suspect that lying awake at night obsessing over how much MA you're buying each week will tend to contribute to rising pH. Basically, pH goes up.

So, your mission is to keep the pH under control. I don't think that it matters much about big doses versus small doses. And at this point it's not worth obsessing about TA; as long as you keep your pH under control, the TA will eventually sort itself out.

In these early days, I would test pH 2-3 times a week. You really want to keep it under 7.8 if you can. When it gets to that point or higher, try to get it down to 7.5 or so. Repeat as needed. When you find it consistently takes a week to get back up to 7.8, then you can reduce your testing frequency.

Keep track of TA weekly, I think; mainly because the Pool Calculator factors that into figuring how much acid you'll probably need. You'll be doing this often enough that pretty soon you'll just know how much to use. But don't obsess about the TA, as long as the week-to-week trend is stable or downward it's not worth paying any special attention to it at this point.
--paulr

 

[Dabby]

Ok, I received my TFP-100 and just did my first complete test. Here are the results:

FC 6.5
CC 0
pH 7.8
TA 110
CH 280
CYA 60

So, if I'm understanding all the advice and Pool School, pH is high again so I added another 32oz of acid (which I understand I am going to be doing every 5-6 days, at least for the first year. TA and CH are fine. CYA is on the lower end of acceptable. FC is high in relation to CYA so I cut back on the SWG.

Does this all sound right? Is CYA something that would be occurring naturally in tap water? I never added any and I didn't see the PB add any. Just wondering where it may have come from.

 

[dmanb2b]

Sounds like you've got the hang of things. FC of 6.5 is just fine with CYA at 60. I know we advise you can run a slightly lower FC on SWG pools, but being in the non-SWG FC range will not harm a thing, actually you'll have added insurance against algae

 

[PaulR]

Does this all sound right? Is CYA something that would be occurring naturally in tap water? I never added any and I didn't see the PB add any. Just wondering where it may have come from.

The numbers all look reasonable. CYA is not present in tap water; either somebody added it, or somebody used dichlor or trichlor as the initial chlorine source prior to the SWG getting cranked up. Dichlor and trichlor both contain CYA.
--paulr