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

YippeeSkippy

Mod Squad
LifeTime Supporter
Jan 17, 2012
12,067
Evans, Georgia
To be honest I get impatient and use the liquid CYA occasionally. The only thing to remember about it is (besides the higher cost) is that it settles at the bottom of the jug something fierce. You need to really shake it up, add water and keep emptying that jug to make sure you get all of it out of there. Plan on using the entire jug. I imagine with your pool it will add about 25ppm/gallon of CYA.

Maddie :flower:
 
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Rancho Cost-a-Lotta

Silver Supporter
Apr 10, 2018
912
Rancho Cucamonga, CA
For the "sock" method, nylon knee highs or pantyhose legs (don't tell my wife) work best. I use about one pound in each and hang them inside of a 5-gallon bucket. Add some hot/warm water, and let them sock a couple hours. Place the bucket on a step or bench inside the pool and run a hose with fresh water in the bucket. Start squeezing the socks in the bucket as the water flows. Make sure the pump is on to circulate the water. It took me about 45 minutes to an hour to completely dissolve 5 pounds. Leave the pump running and brush to help disperse the CYA.
 
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ModernCha

Well-known member
May 29, 2019
72
Charlotte, NC
Screenshot_20200126-125447.pngHere are my test results today. Is it normal for CH to drop by 50 when adding CYA? I have liquid chlorine and plan to add more. I just wanted to let it dilute. I have more cya in the skimmer so I should get it to 40 soon.
 

ModernCha

Well-known member
May 29, 2019
72
Charlotte, NC
For the "sock" method, nylon knee highs or pantyhose legs (don't tell my wife) work best. I use about one pound in each and hang them inside of a 5-gallon bucket. Add some hot/warm water, and let them sock a couple hours. Place the bucket on a step or bench inside the pool and run a hose with fresh water in the bucket. Start squeezing the socks in the bucket as the water flows. Make sure the pump is on to circulate the water. It took me about 45 minutes to an hour to completely dissolve 5 pounds. Leave the pump running and brush to help disperse the CYA.
Oh and I took the first batch of socks from the skimmer and just swished them around and squezed for 30 minutes which did the trick after letting them soak over night.
 

JJ_Tex

Bronze Supporter
Jul 17, 2019
617
Prosper, TX (DFW)
You are low on FC. On Monday it was 0 and 6 days later it is 1.0. The minimum for a salt water pool is 3.0, with the target between 4 and 6 depending on your final CYA.

With your chlorine being below the minimum for a at least a week, I would be nervous about algae. Have you seen any algae, and did you test for CC?
 

ModernCha

Well-known member
May 29, 2019
72
Charlotte, NC
I just added more aiming to get to 3.0. I am going to restest FC and TC in two hours. My cya is at 35 so that's above the 7.5% ratio but I expect cya to hit 40 as the final stabilizer I have in a sock in the skimmer dissolves. I haven't seen any algae. Probably due to dumb luck and the water has been in the low 40s since early December when the SWG turned off. Any reason my goal would be 4.0 to 6.0 when the SWG is off for the winter? That seems really high. I still don't fully understand why SWG pool needs higher cya levels. I will check pool school.
 

JJ_Tex

Bronze Supporter
Jul 17, 2019
617
Prosper, TX (DFW)
Well, the chart says 3.0 is the bare minimum so I would up it to the target of 5-7. If you start off at the bare minimum you will quickly drop below the minimum and still be at risk for algae.
 

Rancho Cost-a-Lotta

Silver Supporter
Apr 10, 2018
912
Rancho Cucamonga, CA
Just tested and got 3.0 FC and TC and stabilizer of 40. So that follows the chart. Still weirded out calcium dropped by 50.
The CH test is one of the more sensitive to proper agitation and interpretation of the end point. Try retesting. The only way to lose CH is through water loss/exchange. The other chems you added would not have effected the results. A Speedstir helps get more accurate CH test results.
 

ModernCha

Well-known member
May 29, 2019
72
Charlotte, NC
Did a tune up yesterday and things are looking better and better. The magnetic stirrer is fantastic.
FC 4
TC 4
PH 7.6
TA 80
CH 240
CYA 35 ( going to add some next week to get closer to 50 and to drop the PH)
Phos 100(I know it's snake oil but I have the test)
Salt 1500 (upping it once water temps breach and stay above 60?)

Any thoughts? I will add more CH if it rains a lot this week.
 

ModernCha

Well-known member
May 29, 2019
72
Charlotte, NC
We had a nice tornado Thursday. I drained my pool by about 3 inches, 2 times in one day. Once in the morning and then at 2pm when our office decided to close. The pool was near overflow so that was fun. It's raining for 4 days next week so K decided to drain it to 1 inch above the tile line today before testing.

FC 5
TC 5
PH 7.4 ( it was 7.8) I added a pint of muriatic acid.
CYA 45
TA 70
CH 230(was 170) I ordered more CH up.

Water temp is
50
 

jseyfert3

Bronze Supporter
Oct 20, 2017
503
South-Central WI
The magnetic stirrer is fantastic.
Yes it is. Luckily I had read enough on here to get it right away. I can't imagine doing it all by hand.

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?
Do you have the Taylor K-2006 or TF-100? If so, it looks like you are using the 25 mL sample for this test. If you use a 10 mL sample (your test kit has directions for this), you multiply the number of drops by 25 instead of ten. You can't get as fine of a result, but you don't need to be super precise at that level. And it cuts the number of drops you need to add by 2.5x. So for a CH of ~250 you need to add only 10 drops instead of 25 drops.

Around 100 and below I'd continue using the 25 mL sample though. So for your CH you can do 10 mL sample to speed up the test and save regents, but for the TA I'd continue using the 25 mL sample.

Someone else around answered your question, you go till adding a drop makes no color change, then subtract that drop. You may find the extended test kit directions useful: Extended Test Kit Directions Archives - Trouble Free Pool
 

ModernCha

Well-known member
May 29, 2019
72
Charlotte, NC
So my perameters have all been great but I am still seeing large ch fluctuations. I added CH up last Monday to get back up from 230 (we had a ton of rain and I drained the pool heavily) and got 310 after. Testing showed 270 today. I am thinking I tested too soon after adding ch up as I haven't had to drain the pool and water levels stayed constant. Overall things are great and I just wanted to say thank you for everyone's advice.

PH 7.8 dropping this down slightly, only slightly as CSI shows it's fine for winter water temps.
FC 5 I don't think I will even add more trichlor pucks this winter.
TA 80
CH 270
CYA 50
 
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mknauss

Mod Squad
TFP Expert
Bronze Supporter
May 3, 2014
23,066
Laughlin, NV
If you replace pool water with rain water, that will reduce your CH by whatever ratio you exchanged. Rain water does not have calcium in it.

At your levels of CH, use the 10ml water sample for testing. Each drop of reagent equals 25 ppm CH.