Proper CH numbers for a 4 month old pool and other water chemistry questions before I take action.

ModernCha

Well-known member
May 29, 2019
72
Charlotte, NC
Hello,

I have a 4 month old gunnite pool with Pebblescapes Mini Pebble Tahoe Blue as the plaster. The pool is about 17,500 gallons including the spa. I was using a pool guy but he went MIA recently so I am doing the testing myself. Now that I am testing the pool again I am seeing some data that is troubling and I went to Leslie's pool supply to confirm it and their tests showed the same values. I have included their advice as well.

Chemistry is below

Free and total chlorine is 0. Pool guy said this is fine in winter. I am in NC and do not cover or close my pool in the winter. We do use the spa. Thoughts on what course to take? Should I shock and use chlorine tabs for the winter?
Salt is 1500PPM. Since the generator doesn't work in the winter the pool guy and Leslies said don't worry about adding it yet. Concur?
Calcium Hardness = 120. This is freaking me out. Pool guy never mentioned it as an issue. Leslie's said if the pool is normal people often hold off adding it for the first 6 months. Thoughts? I have the supplies to up this.
Cyanuric Acid = 0. Note sure if this ties into chlorine and the question of using it in the winter.
Total Alkalinity = 100. Only good test
PH is 8.0. I am adding Muriatic acid today. Acid demand was 2 so adding 29 fluid ounces.
Phosphates is 300. My pool guy never even tested for this and ignored it. Leslies is saying its very high thoughts on this. I have the product to lower it and then maintain it.
 

mknauss

Mod Squad
TFP Expert
Bronze Supporter
May 3, 2014
23,066
Laughlin, NV
Welcome. Can you tell us what test kit you have? And what is the source of the results you show in your post?

You need to maintain your FC based on FC/CYA Chart in your area. You need to get a minimum of 30 ppm CYA in the water.
Your CH should be a minimum of 250-300 ppm. We use CSI (calculated by PoolMath) to see if your water is aggressive to your plaster or scale prone. If your test results are accurate above, and your pool water temperature is ~50F, you are OK right now. But be careful if you lower the pH. And when the water warms, you will need to add calcium.

Phosphates are of no concern. Big money maker for Pool Stores. They just do not matter as long as you maintain your FC based on your CYA level.

Review ABCs of Pool Water Chemistry
 

ModernCha

Well-known member
May 29, 2019
72
Charlotte, NC
Welcome. Can you tell us what test kit you have? And what is the source of the results you show in your post?

You need to maintain your FC based on FC/CYA Chart in your area. You need to get a minimum of 30 ppm CYA in the water.
Your CH should be a minimum of 250-300 ppm. We use CSI (calculated by PoolMath) to see if your water is aggressive to your plaster or scale prone. If your test results are accurate above, and your pool water temperature is ~50F, you are OK right now. But be careful if you lower the pH. And when the water warms, you will need to add calcium.

Phosphates are of no concern. Big money maker for Pool Stores. They just do not matter as long as you maintain your FC based on your CYA level.

Review ABCs of Pool Water Chemistry
I have the leslies DPD pool care test kit made by taylor. I also had leslies pool care test my pool water which confirmed my results.
 

ModernCha

Well-known member
May 29, 2019
72
Charlotte, NC
1579556338934.pngHere is my pool math calculator with CSI. So in order of operations should I raise my calcium hardness, lower the ph or address the CYA and chlorine levels?
 
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mknauss

Mod Squad
TFP Expert
Bronze Supporter
May 3, 2014
23,066
Laughlin, NV
If your water temperature is that low, the FC and CYA are not a threat right now. You should address them soon, however. Salt can wait until your water warms into the 50F's as that is when your SWCG will take effect.

I would suggest adding a FAS-DPD test kit. And do not use test results from a pool store.

Raise your CH but do not lower your pH.
 

ModernCha

Well-known member
May 29, 2019
72
Charlotte, NC
OK, I will tackle the CH levels and get supplies to tackle the FC and CYA this week.
If your water temperature is that low, the FC and CYA are not a threat right now. You should address them soon, however. Salt can wait until your water warms into the 50F's as that is when your SWCG will take effect.

I would suggest adding a FAS-DPD test kit. And do not use test results from a pool store.

Raise your CH but do not lower your pH.
Thank you so much! I added 181 ounces of Leslies hardness plus (about half the needed dose). I will retest and then add more until I hit 350. I will go get chrlorine tablets and CYA tonight. I really shouldn't of trusted the pool guy. Seeing so many things out of whack and trusting him that we didn't need chlorine was a huge mistake and frankly I didn't know what to fix first. After I get CH, CYA and FC to the desired level. Should I adjust PH if that is still required?
 
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mknauss

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May 3, 2014
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Laughlin, NV
As long as pH is 8 or lower, no action is needed on it.
You can use the trichlor for awhile. They are very acidic so they will push the pH down. Just be aware that they add CYA.
 

ModernCha

Well-known member
May 29, 2019
72
Charlotte, NC
As long as pH is 8 or lower, no action is needed on it.
You can use the trichlor for awhile. They are very acidic so they will push the pH down. Just be aware that they add CYA.
Ch is now 280-300 after I added the hardness plus. I give a range as the color change started at 280 but went fully blue at 300. Should I keep going or stay put at that level?

I added the trichlor last night in a floater but see zero FC or CYA still and the pH is still 8. The water is 47 and air is 39. How long should it take for the trichlor pucks to dissovle? Should I add some acid to drop the pH or just wait.

thabk you for your guidance!
 

JJ_Tex

Bronze Supporter
Jul 17, 2019
617
Prosper, TX (DFW)
I would wait on the CH and acid.
I would also add liquid chlorine to get your FC up, then the floater can help your FC maintain.

Lastly, it is not usually recommended on here, but with FC and CYA at zero and CH low(ish) would a single bag of cal hypo shock do some good to add mainly FC with some amounts of CH and CYA?
 
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mknauss

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May 3, 2014
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Laughlin, NV
CH is fine.
Pucks will take weeks to dissolve in that cold water.
Use granular CYA. Add using the sock method.
Use liquid chlorine to maintain 3ppm FC at minimum.
 
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Rancho Cost-a-Lotta

Silver Supporter
Apr 10, 2018
912
Rancho Cucamonga, CA
There's nothing wrong with buying supplies from Leslie's, but you'll pay a premium. There are much better values for chemicals at big-box stores like Home Depot, Lowes and WalMart. I'm guessing the pool store got you for a $50 bottle of Perfect Weekly or some other magic potion that will do little to properly maintain your pool (take it back). You spent lots of money on your new pool. Do yourself a favor and invest another $100 or so to buy the quality test kits you need to take care of your own pool. The TF-100 from Tftestkits.net is the best value. You'll need a Taylor K-1766 kit for salinity.
 
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AUSpool

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LifeTime Supporter
TFP Guide
Sep 23, 2015
733
Brisbane, Australia.
Ch is now 280-300 after I added the hardness plus. I give a range as the color change started at 280 but went fully blue at 300. Should I keep going or stay put at that level?

I added the trichlor last night in a floater but see zero FC or CYA still and the pH is still 8. The water is 47 and air is 39. How long should it take for the trichlor pucks to dissovle? Should I add some acid to drop the pH or just wait.

thabk you for your guidance!
Your CH is 300ppm, it’s the end point your looking for, not where it starts to change. Add one more drop and if that last drop makes no difference the end point (and drop count) was at the previous prop. Don’t count the last one that caused no change.
 
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YippeeSkippy

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Jan 17, 2012
12,067
Evans, Georgia
ModernCha, I just want to reiterate what Rancho-Cost-A-Lotta said- you *need* a better test kit. Yours is lacking the FAS-DPD test which measures FC at higher than 5ppm, and also tests for the Combined Chloramines (the icky stuff).

You can buy just that missing element at www.tftestkits.net FAS/DPD Chlorine & CC's test
Or get an entirely new base kit (TF-100 is my pick).

You can manage your pool and water so much easier with the right equipment. A *good* test kit is an investment that actually will *save* you money.

Maddie :flower:
 
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ModernCha

Well-known member
May 29, 2019
72
Charlotte, NC
I am ordering the additional tests and a magnetic mixer because I hate swirling. I have the CYA in socks in the skimmer(about 3.5ibs to start). But since I need to add so much would it benefit me to simply buy some liquid CYA add today and then add chlorine tomorrow. As the Granular has been in the pool for 12 hours and is very slowly dissolving or is there no real rush seeing as the water is 45 and it's winter. Sorry I am typically a perfectionist so the idea of having my water chemistry be wrong for so long is bugging me even if it presents no immediate issues. Also the pool guy didn't seem to mind being fired which was nice.
 

Texas Splash

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The granular CYA will dissipate quicker if you are able to squeeze the socks more often. With the water that cold, there's no rush to increase the CYA too high (i.e. 70) for your SWG since the SWG can't operate in cold water. Just continue to manage your water as a non-salt pool per the FC/CYA Chart. You can add more CYA when the water temp increases to about 60 or more. The pH can hoover in the upper 7s with the cold water as well. The magnetic stirrer and FAD-DPD will be a BIG help.
 

ModernCha

Well-known member
May 29, 2019
72
Charlotte, NC
I have been squeezing it when I can. I did so this am and swirled them in the skimmer as well. My CYA goal was 40 for now so I can get some chlorine in. Then it will probably creep up via the trichlor tabs all winter so by spring I should almost be at 60. I might be way off there but I have enough product now to add as needed.
 

BowserB

Silver Supporter
Jul 29, 2018
184
Katy, Texas
A couple of things I see here are puzzling to me. The OP says his FC is -0-, and he uses the spa. 100 degree water and 3 or 4 bathers (just guessing they have guests and they're not polar spa people) with zero chlorine. That's OK? Ever heard of Pseudomonas folliculitis ("hot tub rash?") Giarda (OK, that's chlorine-tolerant); Shigella, Norovirus, Legionella, E. Coli? You guys are the experts, and I've just been learning over the last year and a half, but if the OP lived next door and asked me, I'd tell him go get some liquid chlorine from your Leslies store and get your FC up to 3 before you get people in that spa again. But no one here seemed bothered, so please explain, if you have a moment. Oh, I didn't mention Cryptosporidium, but then that's also chlorine tolerant.

Also on the big picture of test results and goals, I see a CYA goal of 70-80, and that is because it is a salt pool? Otherwise it seems a rather high goal. Still learning.
 

YippeeSkippy

Mod Squad
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Jan 17, 2012
12,067
Evans, Georgia
You're right, Bowser. He certainly does need chlorine in that spa if he's still using it. Perhaps @ModernCha can address that?

Otherwise we''ve been discussing the pool's need for CYA and a Salt Water Chlorinating Pool needs a higher CYA than one without a SWCG.

Maddie :flower:
 
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ModernCha

Well-known member
May 29, 2019
72
Charlotte, NC
I was hoping to get CYA up to 30-40ppm today and add chlorine tomorrow but the CYA is taking ages to dissolve. I have not used the spa since before my first post but in truth I doubt my pool/spa was ever properly chlorinated now as I clearly don't think my pool guy was trust worthy (seems like a trend in the pool industry). At this point I am debating just going to Leslies and getting some liquid CYA and Chlorine to get to a base acceptable level. Then just manages things this winter with either trichlor or liquid chlorine until spring and only add granular CYA if needed.