Made a big mess this year, switching to SWG and balancing water

jbrinkerhoff

Bronze Supporter
May 29, 2023
35
Auburn, NY
Pool Size
12500
Surface
Vinyl
Chlorine
Salt Water Generator
SWG Type
CircuPool Edge-25
Upstate NY, 12.5K gal above ground vinyl pool. Added Circupool 25K this year. Started balancing water and added salt. I screwed up something bad, and I'm not even sure how I messed up so bad.

I bought new test strips (yeah, I know) and they showed pH was low, so I bought some pH UP, and added according to the probably terrible instructions on the bag. Tested the next day, and used my drop test kit with new bottles (just the cheap ones). pH was purple, off the chart high. I thought something must be wrong, since the test strips showed pH about 7.6. Test strips also showed ALK was low, and based on that number I added 4lbs of baking soda.

Clearly I am messing stuff up worse, pool became cloudy.

Meanwhile, I am running the SWG and my test strips show salt at 3500.

I decided to STOP and take water to the pool store where they have a computerized tester. They ran it and told me I was all kinda screwd up.

FC 0.4
TC 3.52
CC 3.11
pH 7.6
ALK 150
Calc Hard 84
CYA 14
Iron 0.1
Copper 0.1
SALT 4000

Told me to add 1 gal of Muriatic Acid with the pump off, in blobs around the edge, and wait overnight. Then turn pump back on and wait for a day and bring back in to test.

Then I remembered this website, and came over here and started reading. This morning I tested (drop test) and ph was 6.8. Tuned on the pump and turned off the SWG, and aimed the return to the sky. Making a nice bubble fountain. I will leave it this way until pH comes back up as far as it will. How long shoud this take? Can I shock while this is happening or do I wait?

Looking for help. I am ordering the T100 test kit today. I want to make sure my pool doesn't turn into an algae pit (very very sunny this week, but at least the pool is still cold, 68F). I can use the pool store testing until the test kit comes, and/or the walmart drop test. The test strips are apparently pretty useless?
 
I am ordering the T100 test kit today.
This says it all. No need to do anything else based on all those other numbers above. They are not reliable. For now, just add about 3-4 ppm of liquid chlorine to the water each day. Might as well give the SWG a break during this period. Once you get the kit, post a full set of numbers and we can definitely help get you back on track.

Welcome to TFP! :wave:
 
After bubbling for 2 hours, I tested again, pH still 6.8. I know I have to wait for a real test kit, although I have no reason to assume that the pool store's expensive computer is totally wrong. Either way (for better or worse), I already did the acid add last night before coming here, and am bubbling now. How long until I start to see an increase in pH? I mean, hours or days ballpark? Also, can/should I start to add CYA now while I am waiting? I know its low (I had to add a lot of water this year).
 
although I have no reason to assume that the pool store's expensive computer is totally wrong.
The computer that is designed to sell you chemicals ? Somebody posted their bioguard printout a few weeks ago, and it had *8* spendy chemicals to buy on it.

If they turn you away because the water tests great, there is no sale.

They don't exist to help you, they exist to profit. 🤷‍♂️
 
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How long until I start to see an increase in pH? I mean, hours or days ballpark?
Sounds like it will be days, seeing how it's already been hours. No two pools react the same.
Also, can/should I start to add CYA now while I am waiting?
Not without a relaible test result. CYA is arguably thier least reliable, although I do believe it's low at the moment also. But still. Without proof, it's just a guess and overshooting will mean draining.
 
Thanks everyone for the help. Looking for a bit more advice to get me through the next few days until the new T100 test kit arrives. The one reliable test I seem to have is my pH test (I compared it with my reef tank test and they match pretty closely).

After adding the acid 2 nights ago (above post) the pool dropped to 6.8 as noted. I aerated it all day yesterday, and all night last night. This morning it has increased to 7.2. This sounds good. I ran a dip stick test for the ALK, and although I realize these are not reliable/accurate, it did drop one "notch" to "120" from the 160 it was and the 157 that the pool store tested at before telling me to add acid. I will keep aerating today and see if pH will get to 7.5.

It is super sunny here this week. Probably the next 10 days or more. Pool is warming rapidly - like 6 degrees just yesterday. I do not want turn it into a algae pit.

I did order the T100+salt test kit Sunday, hopefully that arrives later this week. In the meantime:

(Pool store test)
FC 0.4
TC 3.52
CC 3.11

These numbers align with what I can test with the kits I have (OTO and strips).

This looks like I need to shock it badly. I normally would have done that as soon as pH and ALK were in range (in other years before I decided to experiment with the SWG). This year I turned on the new SWG when still balancing the pool which has put me in this situation. Do you think it would be safe for me to shock the pool tonight (pool store recommends 4lbs of their shock, I calculate 2 gallons of 10% liquid which is what I usually would use) and at least get it somewhere that I can prevent it turning into a massive algae mess? My CYA is still low (14 according to store, "below 30" according to my test). I think I can wait on adjusting this until after the T100 test kit comes.

I also think my salt levels are too high, probably 4000 or a bit more (test kits shows 4000+ish). I'm sure these will come down as I backwash and refill with city water. I have noticeable salt forming anywhere water has pooled and evaporated.

EDIT: Gave the filter a big backwash earlier (until the skimmer almost sucked air) and filled back up with the hose with the pump on. Probably about 10% new water (This is fine, I wanted to lower the salt a bit too).
Just went to lunch and stopped at the pool store and had them test again. (Should at least be consistent with the prior results from them?)

FC 0.18
TC 0.51
CC 0.33
Ph 7.5
ALK 103
CH 79
CYA 5

This makes sesne, since I have had the SWG off for the last 24+ hrs and its super sunny, and I washed out quite a bit of water over the past couple days since their last test (CYA). Said it all looks good except chlorine/stabilizer. Really I just wanted the test to compare. Pool is still aerating.

I plan to shock it after dark tonight (2 bags of 73% cal hypo), and run the SWG until my test kit arrives.
 
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You should add 1/2 gallon of 10% liquid chlorine daily until you get your test kit. This will keep things from getting worse until you know for sure where your levels are. Use
PoolMath if you have a different % of bleach. Stay away from powdered shock.
 
Update: Ran filter 24/7 and SWG on full the past few days. Vaccumed up anything. Water getting pretty clear. Dumped 2 gallons of 7.5% bleach in last night after dark, as the water was almost 80F and I was getting really worried about algae starting. Chlorine (test strips/OTO) was "Zero" all day Wed/Th. 30 mins after adding 2 gallons it was "off the chart" >5 for both free and total. Checked after 3 hrs, and it was ZERO AGAIN. In the dark, no sunlight. I did see a fair amount of "foam" on the surface and going into the skimmer. I assume these were oxidized organics. Checked this AM and CL still zero as well.

Today:
Test kit came about 15 mins ago, here are my readings:

TA: 110
Salt: 4400 (!) - I guess the pool store guy wasn't kidding when he said "You won't need ANY salt for a while!"
PH: 7.2
FC: 0.5 (BARELY pink, I mean, BARELY. One drop cleared it)
CC: 0.5 (Back to BARELY pink, and again one drop)
TC: 1.0 (If I did this right)
CYA: "Less than 20" - I could not get it to the point where I could not see the dot at all. I'd say maybe 10-15 tops.

Next steps?

I'm thinking - I want to get the salt down to 3500. Which means dumping water. So no point in adding CYA until I dump water, replace, and re-test. (Our city water rarely affects pH or Alk in a bad way). Right?
 
I'm thinking - I want to get the salt down to 3500. Which means dumping water. So no point in adding CYA until I dump water, replace, and re-test.
That makes sense. Do that first then get the CYA up to 30 since I assume your next step after that is the SLAM Process correct? To take care of the cloudy water/algae? With a CYA of 30 your FC SLAM level will be "12". Do your best to maintain that level using liquid chlorine and follow everything on the SLAM Process page and you should do well. Nice to see you with a proper test kit now. Don't forget to add it to your signature details.
 

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I guess I'm curious about the CYA level - I see that 30 is the minumum, but then I see that for SWG pools higher is often recommended. 50-60. Probably makes sense to raise that AFTER the SLAM, since higher CYA = more chlorine to SLAM?
 
Probably makes sense to raise that AFTER the SLAM, since higher CYA = more chlorine to SLAM?
Winner winner chicken dinner !!!!

You need 30 to SLAM or the sun will eat more FC than the algae. But hold at 30 for a 12 FC target instead of 28 FC target for 70 CYA (typical SWG level)

Get the FC up asap. You'll waste 1/4 gallon by draining and it's worth every penny as insurance.
 
Drained 15% of pool water (per calculation on the app) to lower Salt to ~3500. Refilling now. Will add 2lbs CYA and let it dissolve, that should put me right around 30 or a little low. I will run a full test again in the morning for all parameters before proceeding. Thanks for all the help.
 
tested after CYA and it was right at 30. Waited till sun was down and Added 1.5gal 10% liquid chlor per the calculator, and it topped out right at FC 12. CC at 0.5 Perfect. Leaving it overnight and will test again in the pre-dawn am.
 
Why not test and replace FC every 2 hours until you go to bed? Will get you a jump start!

As @Newdude says, I'm "extra"...my only slam, I slammed every 2 hours, 18 hours a day. I wanted it FiXED!!!!
 
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Why not test and replace FC every 2 hours until you go to bed? Will get you a jump start!

As @Newdude says, I'm "extra"...my only slam, I slammed every 2 hours, 18 hours a day. I wanted it FiXED!!!!
Lol I did mine every 2 hours for over a week then went to 3 times a day, then back to every 2 hours until oclt passed 😂😂 talk about "extra"
 
OK -Holy cow learning curve ahead... LOL.

Anyway, I did my first SLAM. As calculated I kept FC at 12 for 24+ hours, and did the overnight test. (Which means getting up mighty early this time of year!). I think my pool was already pretty close since I had "shocked" it 2 days before the old fashioned way. I dont think there was much left to burn out.

So after the SLAM, FC stayed right at 12, and CC was at zero. So I figured I was done. I let the FC drop in the sunshine to normal range (~3) and at the end of the day Saturday after swimming in the pool all afternoon I added 2lbs stabilizer (target 50) tossed the solar cover on, and turned on my new SWG. No idea where to start with that so I left it at defaults (3/6 - 50% I believe). Sunday was cool so I didn't look at the pool at all and totally forgot about it, and today (monday am) I just tested it:
pH 7.3
CYA 50
FC 16.5 (!!!)
CC 0

I guess my SWG is too much! So I shut it down, pulled back the solar cover, and will let the sun hopefully burn out some of this Cl. Looks like I did an inadvertent 2nd SLAM...

Any help on setting up the SWG? I usually run my pump 24/7 in the summer, but I could go back to using the timer 12h on/12h off (new pump is also 1HP and moves a LOT more water than the old one). SWG is on whenever the pump is on.

I guess my plan is: Wait for pool to get down to ~1-3 FC, its very sunny so hopefully this happens in a day or so. Then turn the SWG back on at lowest setting and re-test every 6hrs or so to see where it goes. If the lowest setting is too high, then I guess I have to go with a timer (for either SWG or pump).
 
OK -Holy cow learning curve ahead... LOL.

Anyway, I did my first SLAM. As calculated I kept FC at 12 for 24+ hours, and did the overnight test. (Which means getting up mighty early this time of year!). I think my pool was already pretty close since I had "shocked" it 2 days before the old fashioned way. I dont think there was much left to burn out.

So after the SLAM, FC stayed right at 12, and CC was at zero. So I figured I was done. I let the FC drop in the sunshine to normal range (~3) and at the end of the day Saturday after swimming in the pool all afternoon I added 2lbs stabilizer (target 50) tossed the solar cover on, and turned on my new SWG. No idea where to start with that so I left it at defaults (3/6 - 50% I believe). Sunday was cool so I didn't look at the pool at all and totally forgot about it, and today (monday am) I just tested it:
pH 7.3
CYA 50
FC 16.5 (!!!)
CC 0

I guess my SWG is too much! So I shut it down, pulled back the solar cover, and will let the sun hopefully burn out some of this Cl. Looks like I did an inadvertent 2nd SLAM...

Any help on setting up the SWG? I usually run my pump 24/7 in the summer, but I could go back to using the timer 12h on/12h off (new pump is also 1HP and moves a LOT more water than the old one). SWG is on whenever the pump is on.

I guess my plan is: Wait for pool to get down to ~1-3 FC, its very sunny so hopefully this happens in a day or so. Then turn the SWG back on at lowest setting and re-test every 6hrs or so to see where it goes. If the lowest setting is too high, then I guess I have to go with a timer (for either
Don't let FC get that low. You should target 3-8ppm with 50ppm CYA. I would never let my FC get below 4ppm. You could turn off the SWG, but remember to keep testing, and when it gets to 5-6ppm FC, then turn on SWG to the lowest setting and see how that works. See this thread for a good FC/CYA chart. You are able to swim in your pool safely up to FC of 20ppm, with a 50CYA.
 

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