Pool Water Chemistry Help

Feb 25, 2019
12
Dallas
Ok I got my water tested today and trying to learn to use the app as well for first time...
FC-1.82
TC-1.82
PH-7.7
TA-84
CH-263
CYA-95
Phos-352

The app is saying target for FC is between 7-13 That seems high to me but not sure based on numbers

I have been trying to get phosphates down and not having the best of luck. It has come down a lot but not in ideal numbers. I have already put a whole bottle of no phos and its still high. When I add shock to the pool it immediately becomes cloudy and takes a whole day to clear up. Never had this happen and just want my pool back to normal numbers and clear.
 

wireform

Silver Supporter
In The Industry
Aug 15, 2017
1,488
Spring Valley, NY
Mad,
I'll just jump in for a second. How are you test. Pool stores don't vote very well here on TFP. Read pool school and get yourself the TF-100 test kit asap from here. Your CYA is high and the FC level is way too low. Check the fc/cya chart to see where your chlorine level should be. That 7-13 may be what it takes for the CYA in your water.
 
Feb 25, 2019
12
Dallas
Mad,
I'll just jump in for a second. How are you test. Pool stores don't vote very well here on TFP. Read pool school and get yourself the TF-100 test kit asap from here. Your CYA is high and the FC level is way too low. Check the fc/cya chart to see where your chlorine level should be. That 7-13 may be what it takes for the CYA in your water.
Yes I am aware Pool stores dont vote well. I had the TF-100 but unfortunately it got crushed by my son recently. Long story but went to get it tested at Leslies. I have order the TF100 though. Sounds like I need to drain some from the pool then bc of CYA correct?
 

Richard320

TFP Expert
LifeTime Supporter
Jan 6, 2010
23,924
San Dimas, CA (LA County)
Yes I am aware Pool stores dont vote well. I had the TF-100 but unfortunately it got crushed by my son recently. Long story but went to get it tested at Leslies. I have order the TF100 though. Sounds like I need to drain some from the pool then bc of CYA correct?
I wouldn't make any big changes based on pool store testing. Draining half the water qualifies as a pretty big change.

How would CYA get so high? Have you been chlorinating with pucks? Doing the weekly shock with dichlor? CYA does just appear, it;s not in tap water ir rainwater. If you've been testing until recently, and followimg TFP, your CYA shouldn't be so high. If you've been feeding it pucks, it may be even higher than 95. What happens if you drain half and then discover you're over 100? You get to drain all that fresh water again.

I suggest you add enough chlorine to get to 10 FC today, and add 3 FC every day until you have your own test results from the new kit I hope you've ordered.
 
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BowserB

Silver Supporter
Jul 29, 2018
338
Katy, Texas
Someone here more knowledgeable than I will shortly say don't worry about phosphates. Get the chlorine and cya right and there won't be any algae to use the phosphates. Everything I've read here says a partial water replacement is how you get CYA down, although each of the two winters we've had a pool here west of Houston, the CYA has dropped a bit on its own...although not as much as you need yours dropped. You didn't specify how you chlorinate, but from the high CYA, I'm guessing trichlor tabs. Pure liquid chlorine is better. 12.5% may be the best value for you in Dallas. At least it is in Houston. Amazingly enough, Leslies is the cheapest chlorine (adjusted for concentration) in our area. You'll find chlorine from 6% to 12.5%. If you're still determined to reduce phosphates, this from what I've read is the best product:
 
Feb 25, 2019
12
Dallas
I wouldn't make any big changes based on pool store testing. Draining half the water qualifies as a pretty big change.

How would CYA get so high? Have you been chlorinating with pucks? Doing the weekly shock with dichlor? CYA does just appear, it;s not in tap water ir rainwater. If you've been testing until recently, and followimg TFP, your CYA shouldn't be so high. If you've been feeding it pucks, it may be even higher than 95. What happens if you drain half and then discover you're over 100? You get to drain all that fresh water again.

I suggest you add enough chlorine to get to 10 FC today, and add 3 FC every day until you have your own test results from the new kit I hope you've ordered.
We have been out of town for 3 weeks on and off and it was crushed about a week before we left. Just had too much going on, like moving a business as well. I use pucks in an inline feeder. We have had a lot of weird storms here compared to normal while gone and just yesterday as well. And yes we have been doing weekly shocks when I have refilled the pucks once a week. Just being honest I have just maintained what I am doing and testing has been delayed. Now trying to get back on track.
 

Chasarms

Silver Supporter
May 8, 2020
345
Dardenne Prairie, MO
We have been out of town for 3 weeks on and off and it was crushed about a week before we left. Just had too much going on, like moving a business as well. I use pucks in an inline feeder. We have had a lot of weird storms here compared to normal while gone and just yesterday as well. And yes we have been doing weekly shocks when I have refilled the pucks once a week. Just being honest I have just maintained what I am doing and testing has been delayed. Now trying to get back on track.

The use of the trichlor is almost certainly what has elevated your CYA. If the @100 CYA is confirmed, you are going to have to keep FC at the high recommended targets to keep the pool sanitized.

Once you have confirmed the CYA ppm, your options are to drain about half your water and refill, or maintain the high FC targets until the CYA burns off, which will take a LONG time. In either case, you should strongly consider switching to liquid chlorine to avoid elevating the CYA levels even further.
 

duraleigh

Admin
Mod Squad
TFP Expert
Platinum Supporter
LifeTime Supporter
In The Industry
Apr 1, 2007
34,280
Sebring, Florida
I suggest you add enough chlorine to get to 10 FC today, and add 3 FC every day until you have your own test results from the new kit
That's really good advice and, for heavens sake, please ignore phosphates
 
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Feb 25, 2019
12
Dallas
UPDATE and would like input if possible. My test kit came in and my CYA was at 90 and it was hard to keep that much chlorine in the pool in Texas. So I decided to go ahead and drain part of the pool. Once I was done (may be wrong but did it anyway) I added a packet of shock out of fear the tap water didnt have enough chlorine in it. So after 24 hours of pump running with shock and new water I just did a new water test. Here are the numbers...

PH-7.5
FC-10.5
TC-11.5
Calcium-325
TA-120
CYA-50

I know the TA looks a little high but could this be because of the city water and just needs time to settle/mix? Or should I go ahead and add acid? Just afraid of doing yet because could through off PH.
 

Jeff J.

Well-known member
Aug 6, 2019
214
Staten Island NY
Maintain the CSI between -0.3 and 0.0.


As James said, as long as your CSI is okay and your PH is stable, there's no need to adjust your TA.