Chlorine and pH

DanL

Active member
Nov 23, 2016
35
Las Vegas NV
First, I promise I did read Pool School and searched and read many previous threads. Sorry, but I think I got even more confused trying to digest it all. Just need some guidance for a couple next steps.
Pool info is in signature line.
I'm a part-year resident and had a supposedly weekly pool guy. We just let him go when we returned because he wasn't showing up. He said no worry, pool was in great shape...clear water, etc etc., but I decided to take over pool care. As reco'd here, I ordered a TF 100 test kit. Just checked water with the R-0600 for chlorine and R-0014 for pH. Chlorine color was brown and pH dark purple, both off-the-scale high. I checked the floating puck chlorinator and it had 3 pucks in it. Seems his approach was add a ton of chlorine and come back every so often.
I removed the chlorinator and now trying to decide what the most sensible next steps are. Additional tests? Chlorine reducer? Muriatic acid? Sorry to be asking, the info here is really great, but I'm just a bit overwhelmed as I start into this.
Notes...water T is 50-55deg, pool uncovered, I reset pump to run 5hrs/day@2650rpm and cleaned the filter, water is clear, pool surfaces are totally clean.

EDIT: Just took sample to pool store. Their test indicates very high solids, high pH (told to add 3 cups acid), and "perfect" chlorine level. I'm now really confused. Back to Pool School....
 

triptyx

TFP Guide
Apr 12, 2016
1,495
Tucson, AZ
That's ok! There's a lot of info there and it can be overwhelming. We're just happy to have you here. :)

The chlorine will burn off over time - the sun and the process of it doing its job killing bad things will bring it down normally and naturally. You can't test pH with any reliability until the chlorine level (FC) is at 10 or below - so for the moment, just sit tight and let that chlorine burn off. Make sure you leave any solar blankets or other pool covers off to assist in the process.

Do you have your TF-100 yet? If you do, let's try a complete set of tests except for pH to see where you are. If you don't, sit tight until the TF-100 arrives and then give us a full set of test results (again, without pH until that FC level comes down). Let the water sample for the CYA test come up to "room" temperature before you test it - I understand cold water can cause it to read funny.
 

Mr Bruce

TFP Guide
Mar 24, 2014
2,095
Greenville, SC
If the OTO chlorine test is brown, the pH test will be invalid. I would just let the chlorine drift down while you wait on your kit, do a full test with it and go from there.
 

pabeader

LifeTime Supporter
TFP Guide
May 14, 2015
4,349
Cartersville Ga
First, I promise I did read Pool School and searched and read many previous threads. Sorry, but I think I got even more confused trying to digest it all. Just need some guidance for a couple next steps.
Pool info is in signature line.
I'm a part-year resident and had a supposedly weekly pool guy. We just let him go when we returned because he wasn't showing up. He said no worry, pool was in great shape...clear water, etc etc., but I decided to take over pool care. As reco'd here, I ordered a TF 100 test kit. Just checked water with the R-0600 for chlorine and R-0014 for pH. Chlorine color was brown and pH dark purple, both off-the-scale high. I checked the floating puck chlorinator and it had 3 pucks in it. Seems his approach was add a ton of chlorine and come back every so often.
I removed the chlorinator and now trying to decide what the most sensible next steps are. Additional tests? Chlorine reducer? Muriatic acid? Sorry to be asking, the info here is really great, but I'm just a bit overwhelmed as I start into this.
Notes...water T is 50-55deg, pool uncovered, I reset pump to run 5hrs/day@2650rpm and cleaned the filter, water is clear, pool surfaces are totally clean.

EDIT: Just took sample to pool store. Their test indicates very high solids, high pH (told to add 3 cups acid), and "perfect" chlorine level. I'm now really confused. Back to Pool School....
Note: Don't let the pool $tore testing confuse you. They are rarely correct, and as you found out, they are often way off.
 

tim5055

Mod Squad
TFP Expert
LifeTime Supporter
May 11, 2014
10,122
Franklin, NC
If all,the pool guy has been throwing at the pool are pucks and shock, I'd be interested in seeing what the CYA level is. The other levels,will have no effect on the CYA test". Just take a water sample and let it warm to room temperature before you conduct the test.

As Bob said, stay away from the pool store. Ignore "solids", that is just a way for them to sell you stuff you don't need.
 

DanL

Active member
Nov 23, 2016
35
Las Vegas NV
Summary of Day 1 (see first post):
All results with new TF 100 test kit.
Yesterday, on day1, I used the TF100 test kit to test Cl and pH. Both were off the scale high.
Took water to pool store. They confirmed hi pH, but said Cl level was fine. Also said pool needs water change due to high solids.
Told me to add 3 cups muriatic acid. I added the acid.

Day 2:
Rechecked Cl and pH. Cl was dark orange, still off-scale high. pH is now down to 7.8 after adding acid yesterday. (new kit, fresh reagents dated 5/18, water T=60F)
Ran CYA...result much greater than 100....rough extrapolation about 130.

Going back to research here on TFP, but any helpful comments welcome.
 

triptyx

TFP Guide
Apr 12, 2016
1,495
Tucson, AZ
You have your TF-100- awesome!

Please run the FAS-DPD test using a 10ml water sample (divide the number of drops needed to change color by 2 to get your results) and let us know what that test says the Free Chlorine is please.
Please also run the CYA test using the dilution method, first letting the water temperature rise to something approximating room temperature. To dilute it, mix one part pool water and one part tap water, then use that mixed water sample to put in the little snuffer bottle. Multiply the results by 2 to get an approximate CYA result. Anything under 100 on the view tube is invalid, so we have to dilute it to get a better approximation.

Please do not add any more acid until the FC level is below 10, the pH test does not work with an FC over 10. :)
 

steveb21

Well-known member
Mar 6, 2017
199
United Kingdom, England.
Summary of Day 1 (see first post):
All results with new TF 100 test kit.
Yesterday, on day1, I used the TF100 test kit to test Cl and pH. Both were off the scale high.
Took water to pool store. They confirmed hi pH, but said Cl level was fine. Also said pool needs water change due to high solids.
Told me to add 3 cups muriatic acid. I added the acid.

Day 2:
Rechecked Cl and pH. Cl was dark orange, still off-scale high. pH is now down to 7.8 after adding acid yesterday. (new kit, fresh reagents dated 5/18, water T=60F)
Ran CYA...result much greater than 100....rough extrapolation about 130.

Going back to research here on TFP, but any helpful comments welcome.
im sure that if the CYA is over 100 then a partial water drain will be required. Im sure there will be some one else along soon to provide more in depth advice.
 

DanL

Active member
Nov 23, 2016
35
Las Vegas NV
Summary of Day 1 (see first post):
All results with new TF 100 test kit.
Yesterday, on day1, I used the TF100 test kit to test Cl and pH. Both were off the scale high.
Took water to pool store. They confirmed hi pH, but said Cl level was fine. Also said pool needs water change due to high solids.
Told me to add 3 cups muriatic acid. I added the acid.

Day 2:
Rechecked Cl and pH. Cl was dark orange, still off-scale high. pH is now down to 7.8 after adding acid yesterday. (new kit, fresh reagents dated 5/18, water T=60F)
Ran CYA...result much greater than 100....rough extrapolation about 130.

Going back to research here on TFP, but any helpful comments welcome.
OK...repeated CYA with 50/50 pool/filtered water, about 70F. New result just over 100. So CYA is 100 x 2= 200+ (Note...tested dilution water...0 CYA....perfectly clear)
Also checked chlorine reagent (R-0600) on city tap water. Got 1-2. City spec is 0.8 avg, max 1.6, so reagent is right on. Still wonder how I get orange brown chlorine result from pool water.
Holding off on other tests...looking into draining the pool and refill.
 

triptyx

TFP Guide
Apr 12, 2016
1,495
Tucson, AZ
Gah. Sorry to hear about the refill. :(

I did it myself last April for the same reason, and it was totally worth it. Make sure you look into your local city and county regs on disposing of pool water, and I'd recommend the rental submersible pump from Lowes or Home Depot. You'll also want to do this before it starts getting hot (but after your annual sewer bill usage is calculated - if they do that in LV). The plaster can't be allowed to bake in the sun - it needs to be kept cool and moist during the drain/fill.
 

needsajet

TFP Expert
LifeTime Supporter
Jan 4, 2016
4,594
Sydney, NSW, Australia
Your priority is the drain/refill, and your helpers will describe some things to be careful about, but definitely that's the priority.

Later on, when you get back to testing FC... there are two chlorine tests in the TF-100. You're using the OTO test, which turns yellow, orange or brown. It's useful as a quick check for presence of chlorine, but not the better choice for determining your actual chlorine level.

Once you get the CYA down, you can start using the other chlorine test, called FAS-DPD. DPD is a powder (R-0870) which is added first and which will turn the water pink when there's chlorine in the water. You then use the FAS titrating reagent (R-0871) drop-wise to determine the chlorine level.

Sorry to hear that your pool guy went crazy with the pucks and wrecked your water with CYA :(
 

DanL

Active member
Nov 23, 2016
35
Las Vegas NV
Thanks everyone. Info much appreciated.
Day 3: Rented pump at HDepot, pumping out now. Pump rated at 2700gph. I calculated volume of the water in the top 1ft layer of the pool....500sqft x 1ft = 500cuft = 3,700g.
The pump lowered the water by 9" in the first hour. Doing the math...9"/12" x 3700g per 12" = 2775gal. Wow... really right on the rated pump rate.
Plan to do almost 100% water change (hasn't been done for four years). Water cost will be about $65 and pump rental was $42.
Next: de-scale...bad/thick line of white scale all around pool. Trying Descale-It 100% Biodegradable descaler followed after soak time by scraper and green pad. Soften/dissolves deposits a bit, but will not be the total answer.

Now going to get chlorine at Walmart to wash pool surfaces before refill even though the below water surfaces seem very clean. Going to Pool School next on refilling steps, adding chlorine etc. Plan to use liquid chlorine bleach...no more pucks. City water for refill measures 1-2ppm chlorine, spec'd at 0.8-1.6.

Any comments, advice appreciated.
 

kimkats

Mod Squad
LifeTime Supporter
Jul 10, 2012
37,569
Tallahassee, FL
The white scale-1 to 4 muriatic acid to water in a spray bottle BUT know that m. acid will lower your PH. So long are you are aware of this all is good and you can "fix" it as needed when the time comes.

Kim:kim:
 

DanL

Active member
Nov 23, 2016
35
Las Vegas NV
The white scale-1 to 4 muriatic acid to water in a spray bottle BUT know that m. acid will lower your PH. So long are you are aware of this all is good and you can "fix" it as needed when the time comes.

Kim:kim:
Kim,
Thanks!
While pool is being pumped out, I will start cleaning. Plan to finish all cleaning and maintenance before refilling. I'll try the diluted acid.

My next step is learning how to calc the amount of bleach I'll need to add to the new water.
 

kimkats

Mod Squad
LifeTime Supporter
Jul 10, 2012
37,569
Tallahassee, FL
Got that covered on my siggy below! Look for Pool Math. There is a learning curve so play around with it to get used to it.

Kim:kim:
 

triptyx

TFP Guide
Apr 12, 2016
1,495
Tucson, AZ
Don't forget while it's draining to remove the lights from their niches and spray/scrub the niches out. I got all kinds of nasty crud out of mine.
 

domct203

Bronze Supporter
LifeTime Supporter
TFP Guide
Jun 3, 2015
3,959
CT
You really only need to drain 75-80% or so, you will want some CYA in there.
 

DanL

Active member
Nov 23, 2016
35
Las Vegas NV
You really only need to drain 75-80% or so, you will want some CYA in there.
Day 4: Emptied pool yesterday. Did some acid wash and Descale-It on some areas....most of underwater surfaces looked vey clean. Rinsed thoroughly and pumped out all rinse water. Started refill at 7pm...2 hoses and autofill = 650gph, so 16,000g pool/spa should be full by 7 or 8pm today.
Checked CYA (TF100)...water is clear. So domct, I will have to raise CYA as you say. I have a bucket of maybe 20 leftover pucks...will be looking at using those and see where CYA goes????
Need to plan next steps on the water chem. Seems first step should be a complete range of tests to know starting point?
 

tim5055

Mod Squad
TFP Expert
LifeTime Supporter
May 11, 2014
10,122
Franklin, NC
I have a bucket of maybe 20 leftover pucks...will be looking at using those and see where CYA goes????
Great job on taking control!!

As you fill add a little bleach to keep the FC up. I would save those pucks for vacations and fine tuning of CYA.

As a CYA start from "0" they are too slow. You can pick up granular CYA at Home Depot or Lowes, usually the pool stuff is in outside garden. Use PoolMath to calculate how much CYA to add to get to 30 for right now. Pour that amount in an old sock and either hang it in front of a return, or as I do just put it in a skimmer (the CYA filled sock, not raw CYA granules). Every 15-20 minutes go by and squeeze the sock. Generally it's gone in a few hours.

Test your pH and adjust

While you are at Home Depot or Lowes pick up CH Up. Test your fill water and I think you will find it is a little high in CH, so this will rise over time - so don't start too high.
 

DanL

Active member
Nov 23, 2016
35
Las Vegas NV
Great job on taking control!!

As you fill add a little bleach to keep the FC up. I would save those pucks for vacations and fine tuning of CYA.

As a CYA start from "0" they are too slow. You can pick up granular CYA at Home Depot or Lowes, usually the pool stuff is in outside garden. Use PoolMath to calculate how much CYA to add to get to 30 for right now. Pour that amount in an old sock and either hang it in front of a return, or as I do just put it in a skimmer (the CYA filled sock, not raw CYA granules). Every 15-20 minutes go by and squeeze the sock. Generally it's gone in a few hours.

Test your pH and adjust

While you are at Home Depot or Lowes pick up CH Up. Test your fill water and I think you will find it is a little high in CH, so this will rise over time - so don't start too high.
Ran tests on new fill water:
71F temp, CH 300, TA 130, CYA 0, pH 7.8, Cl 0. A lot of Ca in Las Vegas water I guess...

So, using Pool Math:

Item/Now/Target/Action
FC/ 0/ 4/ add 87oz of 10% liq. bleach
pH/ 7.8/ 7.2/ add 58oz muriatic (29%)
TA/ 130/ 90/ (take pH to 7.2, aereate using spa overflow)
CH/ 300/ 300/ no action
CYA/ 0/ 30/ add 68oz CYA

Plan to add the CYA today (sock in skimmer). Add half chlorine and acid tomorrow AM. Re-measure and add more as needed in PM.
 

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