Not making sense

Eilum

Well-known member
Jun 19, 2016
102
Jackson NJ
Opened the pool to swamp and these readings

FC 0
pH 8.2+
TA 60
CYA 0

Decided to add CYA and MA to lower pH to 7.2

Based on PoolMath added Stabilizer in sock and MA. But readings came out

FC 0
pH 6.8-
TA 40
CYA 60-70

Added Washing Soda to increase pH according to PoolMath and retested this morning

FC 0
pH 6.8-
TA 30-40
CYA 60-70

What is going on and what do I do now?
 

woodyp

Mod Squad
TFP Expert
LifeTime Supporter
Apr 17, 2010
10,288
East Texas
Are you saying that PH is now a negative 6.8? How much MA was added? Why no chlorine additions if you have a swamp?
 

Eilum

Well-known member
Jun 19, 2016
102
Jackson NJ
Was waiting to have CYA and pH at level before SLAMing. The pH is reading 6.8, the lowest reading, but is actually lower because I added Washing Soda and it is still reading 6.8.
 

kimkats

Mod Squad
LifeTime Supporter
Jul 10, 2012
37,556
Tallahassee, FL
How sure are you of your pool gallons? How did your testing go last summer?

I would work on the PH asap then let us know what happens.

Kim:kim:
 

woodyp

Mod Squad
TFP Expert
LifeTime Supporter
Apr 17, 2010
10,288
East Texas
I'd say recalulate from 6.8 and sneak up on it so as not to overshoot. You can add and retest in 30 minutes or so on PH while circulating.
 

dfahrion

Bronze Supporter
Oct 18, 2013
89
Iowa
What CYA were you shooting for? Usually with 0 FC you would only want to hit 20-30 initially. Also how much MA did you add? Stabilizer is acidic, according to pool math to add enough stabilizer to go from 0-30 CYA it would lower my pH 0.56. Or 0-60 would lower pH 1.11 Did you take that into account when calculating the amount of MA to add?

BTW, sneaking up on 7.2 from a low value is tricky as there isn't much room there to play with unless you can find another way to test how low it really is. I opened to a low pH this year, and it took me quite a while (and half of what I thought was a lifetime stock of soda ash) to get to 7.2. If you forgot to take into account the extra 1.11pH drop from the stabilizer your pH is probably quite low.
 

Eilum

Well-known member
Jun 19, 2016
102
Jackson NJ
Oh boy. Ok, so will work on that pH. But what about the CYA at 60-70? Got to get it down to 20-30 to SLAM. So the only way is to drain half the pool :eek:
 

Eilum

Well-known member
Jun 19, 2016
102
Jackson NJ
Drained out an inch or two (to waste for 15 min or so) and now the pH is back above 8.2.

Can someone please explain to me what is going on with this pool?

To review: opened to swamp 0 CYA and pH 8.2+
added CYA and MA and dropped pH below 6.8
added Washing Soda and retested pH still below 6.8
Tested CYA next morning around 70 when PoolMath said it should be around 30
Backwashed to waste and now pH above 8.2 and CYA high 50s
What's going on?
 

Donldson

TFP Expert
LifeTime Supporter
In The Industry
Jun 12, 2009
3,347
NW Ohio
Are you absolutely positive you had PoolMath set to 30,000 gallons when you calculated your CYA and MA additions? It sounds like you doubled up on everything in that step.
 

woodyp

Mod Squad
TFP Expert
LifeTime Supporter
Apr 17, 2010
10,288
East Texas
Incorrect gallons assumed or entered most likely. Dropping water level ain't the issue.
 

Eilum

Well-known member
Jun 19, 2016
102
Jackson NJ
Ok. Maybe incorrect volume, so only thing to do now is drain more to lower CYA? :(

Funny thing: my daughter was blowing the yard this morning with leaf blower and turns out she enjoyed "making waves" in the pool. Isn't that called aerating and wouldn't that account for the rise in pH?

If so, what do I do now? Drop again with MA or does aerating eventually work itself back down?

This is getting really frustrating!
 

Texas Splash

Mod Squad
TFP Expert
LifeTime Supporter
Eilum, not sure if Woody is on-line, so I thought I'd jump in to answer your last questions:
- The blower? I doubt it had a big effect on pH. PH usually doesn't fluctuate so fast unless something has changed chemically. MA will effect pH (lower it) but stabilizer (CYA) doesn't. As your pH seems to be high (probably dark red/purple on the comparator viewing blocks), you will use MA to lower it. I would suggest for now, go slow and in stages with dosages and retest in about 30 min. To go from 8.2 to 7.3 is about 2 quarts and 1 cup of MA. If you're concerned about going too low, try just 1 quart then compare the result 30 min later. That could help you adjust your pool volume "IF" that's an issue.
- Once the pH is adjusted down to 7.2-7.4, you can start the SLAM even though your CYA is 60. So it's up to you - drain water to lower CYA and use a lower SLAM (FC) level, or stay at a CYA of 60 and use the SLAM/Shock FC level of "24". Totally up to you. If you do decide to drain more water, don't bother adding muriatic acid to lower pH. It will go right into the lawn. Me personally, I'd just stay there (CYA of 60), not drain anymore, and prepare to SLAM once the pH is confirmed. Remember to pour MA (muriatic acid) very slowly near the return jet(s) and let mix for about 30 min then retest. We'll watch for updates and try to help you get back on track.

Hope that helps.
 

Eilum

Well-known member
Jun 19, 2016
102
Jackson NJ
Thanks so much. Just did MA yesterday and not sure how it got back up (did not add that much Soda) but is what it is. So back to MA and will slow down, as you suggested. Isnt FC of 24 going to take alot of chlorine? And that means all summer long I will have to maintain at about 8 - which is also very high. Will have to decide what to do about the drain. Just don't see how this happened, I was trying to be so careful!!

Pools!
 

Texas Splash

Mod Squad
TFP Expert
LifeTime Supporter
Isnt FC of 24 going to take alot of chlorine?
Since there seems to be some questions about your true pool size, I used the Poolmath calculator to estimate. I used 25K as a pool size, and to increase FC from zero to "24" is 7 gallons of regular 8.25% bleach. Of course if you have some FC in there now, you won't need as much. But once elevated to "24" then it's a matter of simply maintaining it.
And that means all summer long I will have to maintain at about 8 - which is also very high.
Don't be so tough on yourself. The elevated CYA keeps the FC safe and helps protect it from the sun. As long as you don't use tablets or add any forms of stabilizer, it will slowly/eventually go down from splashout and backwashing. For what it's worth, I keep my CYA at about 60 (sometimes higher) down here where I'm at because the sun is so intense. You probably don't have quite the same problem, but once you get past the SLAM, it will be fine.
 

Eilum

Well-known member
Jun 19, 2016
102
Jackson NJ
Just wanted to update. Reapplied MA, carefully and slowly this time to get the pH down near 7.2 then started SLAM at the current CYA level. Been about 48 hours and pool looking blue again. Still cloudy but adding DE to sand filter really speeds up the process.

So thank you all!!
 

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