Major problem with SLAM CL levels

[mchimes]

Hey- hoping to get some help with this. I've been using the TFP method for 5 years and I'm very familiar with the tests.

Short version:
SLAMMED the pool due to cloudy water last night (nothing green or yellow). Pool Math told me that adding 3 gallons of LC would bring my FC to 24. But the reading is now 46... it took 96 drops of reagent to make the water clear. Why did it do this? I've done many of these tests and it has never gone that high.

Long version:
1) I converted to SWG three days ago (Circupool RJ-45+) and upgraded to VS pump (Pentair Superflo). This was a DIY job, so my balanced water sat for two days at 1-2ppm of FC while I worked out some piping and electrical snags.
2) I added a phosphate remover (yes, I'm aware of their reputation on the forum) as the level was 4000 and I wanted to start with it closer to 0 according to the Circupool manual. So I wasn't sure if the cloudy water was the phosphates in suspension or the start of algae.
3) I also added too much salt blindly following the pool stores instruction of 6 bags
4) Partially drained/refilled the pool to get the salt to 3800 so the SGW would work- the pump and chlorinator work great
5) Worked the last 2 days to get the water balanced to new SWG levels (lowering TA, raising CYA, keeping pH at 7.5)
6) But the water was still cloudy, not green at all, so I thought it was still the phosphate remover doing its thing
7) Added a new filter last night which usually clears things right up
8) Turned salt cell off and SLAMMED the pool with 10.5% LC according to pool math app recommendations (3 gallons)... measured FC at 45 ppm with CYA at 60.
9) Water still cloudy and very un-swimmable.

So, what happened and how can I get the water into balance? I leave for vacation tomorrow and thought the SWG would keep things blue while I'm gone, not it's all a mess. With that high of CYA, it's going to take forever for the FC to drop to range with no algae present. Do I need to drain/refill a little again? Can I run the SWG very low with the FC levels that high?

Tests pre-SLAM and post SLAM


Test post-SLAM


Thanks,
Mike

 

[PoolStored]

Did you test with 10mL sample of 25mL sample?

If you did 25mL sample, 96 drops would have been FC 19.2

 

[Mdragger88]

Hey Mike
Something is definitely wonky,
Maybe u got lucky & got some super potent bleach
Or maybe you did the drops too fast so they were small? Or perhaps the sample was reverting back to pink while u we’re doing it - this happens with long pauses.
Re test this morning to confirm fc for a start. Using 10ml sample & every drop counts as .5
A fc level that high won’t stick around for long.
The SLAM Process takes time & requires maintaining slam level fc until u pass all 3 end of slam criteria- that generally takes at least a few days even in a clear pool. It’s unlikely u we’re going to accomplish this before u left anyway.
Since u are leaving, you can do your best to maintain slam level until u go & run your swg while you are away. You can definitely run the swg @ slam level fc. I would just set it to produce 5ppm or so a day. Then u can resume SLAM upon your return.

Ps - your screenshots & poolmath logs are two different accounts so they are not cohesive. Be sure u are logged into poolmath w/ the account u are logged in & posting from @Leebo may need to help u sort it out.

 

[Mdragger88]

So I wasn't sure if the cloudy water was the phosphates in suspension or the start of algae.

When in doubt always do an Overnight Chlorine Loss Test.

 

[mchimes]

Did you test with 10mL sample of 25mL sample?

If you did 25mL sample, 96 drops would have been FC 19.2

10mL

 

[Mdragger88]

What poolmath told u was accurate & should have resulted in slam level fc for your cya.
You can also try to test the bleach concentration of anymore jugs from that batch in a 5gal bucket of chlorine free water using 1ml of bleach & see how it compares to poolmath before dosing with it again.

 

[Mdragger88]

10mL

45 drops is 22.5 ppm
Maybe it was late & u counted the #of drops as your final ppm result ?
At any rate - retest.

 

[mchimes]

Hey Mike
Something is definitely wonky,
Maybe u got lucky & got some super potent bleach
Or maybe you did the drops too fast so they were small? Or perhaps the sample was reverting back to pink while u we’re doing it - this happens with long pauses.
Re test this morning to confirm fc for a start. Using 10ml sample & every drop counts as .5
A fc level that high won’t stick around for long.
The SLAM Process takes time & requires maintaining slam level fc until u pass all 3 end of slam criteria- that generally takes at least a few days even in a clear pool. It’s unlikely u we’re going to accomplish this before u left anyway.
Since u are leaving, you can do your best to maintain slam level until u go & run your swg while you are away. You can definitely run the swg @ slam level fc. I would just set it to produce 5ppm or so a day. Then u can resume SLAM upon your return.

Ps - your screenshots & poolmath logs are two different accounts so they are not cohesive. Be sure u are logged into poolmath w/ the account u are logged in & posting from @Leebo may need to help u sort it out.

Thanks for your feedback. I retested and it is now at 40ppm (80 drops), but that doesn't reflect an OCLT, because I panicked last night and drained out some of the high chlorine water and put in fresh water. I just don't know why it spiked so high. Are LC levels boosted when in salt water? I will know more today when the sun hits it. I'll retest tonight and see how much came out. Considering the SLAM level was supposed to be 24ppm, whatever is in there will be very dead by the time this drops down to even the SLAM level.

I guess I can just let it come down slowly and then set the SWG to 50% while I'm gone to have a backstop when it gets to target levels.

 

[wireform]

If you're using the magnetic stirrer make sure you have 10ml water before the white bean is introduced to the mix.

 

[wireform]

40 drops = 20 ppm

 

[mchimes]

45 drops is 22.5 ppm
Maybe it was late & u counted the #of drops as your final ppm result ?
At any rate - retest.

I actually tested twice last night (10mL) for that reason- same result. Then again this morning and it took 80 drops. Don't know why it spiked so high.

If you're using the magnetic stirrer make sure you have 10ml water before the white bean is introduced to the mix.

I do have the speed stir, but I did this by hand swirling with one hand adding drips with the other. I was very careful for all 3 post SLAM tests to make sure it was exactly 10mL. Hey have done this test dozens and dozens of times over the years that’s why I am scratching my head.

One of three things must be true:
1) my baseline chlorine level was off (preSLAM), which I doubt because I measure under 5 ppm and a good tech at the pool store verified
2) the chlorine is way more than 10%
3) something in the system is amplifying the CL reading ( even though the salt sell is off)

What’s also weird is that the brand new 120 sq. Ft. Filter is not clearing the cloudiness after pump running all night at 3450 rpms.

 

[Mdragger88]

Exactly what phosphate remover did u use?

 

[mchimes]

Exactly what phosphate remover did u use?

Thanks for your help. The water is still not clear but improving. The pressure on the filter has not really moved so I don't think it is getting gummy with the phosphate remover (a ran the old filter and cleaned it to catch most of that before installing the new filter).

This is what I used: Suncoast Super Phosphate Remover, Qt.

I just retested after a day of FL sun and about an hour of afternoon rain... the FC dropped 10-12 points since this morning. 32 ppm (64 drops) from the bottom drain and 30 ppm (60ish drops) adding the skimmer bringing in some of the rain water from the top. At this rate it will hit the SLAM recommendation (24ppm) by tomorrow night which I think will have killed anything in there. i still don't know why it spiked with only 3 gallons added.

I plan on turning on the SWG tomorrow night to keep a baseline of CL over the vacation. Was hoping to dial it in before I left, but that didn't happen. At least I don't have to ask my neighbor to dump LC in every other day.

 

[Mdragger88]

Doing an Overnight Chlorine Loss Test will help u decipher if u are actually dealing with algae or just the phosphate stuff.

 

[mchimes]

Doing an Overnight Chlorine Loss Test will help u decipher if u are actually dealing with algae or just the phosphate stuff.

Doing an Overnight Chlorine Loss Test will help u decipher if u are actually dealing with algae or just the phosphate stuff.

Tested last night and this morning and both came back at 29ppm. Ran the filter in max nist of the night and I can see the bottom drain now and water is about 50% more clear.

Going to get my CYA up to 80 today and set the SWG for 50% for vacation. It’s rated for 45,000 gallons and my pool is only 15,000. At 80ppm for CYA, 5% would put my FC at 4ppm. My TA is high but I will just have to address that when I get back.

Going to the Grand Canyon and other parks. Stoked.

Thanks for your help,
Mike

 

[Mdragger88]

Target fc for 80ppm cya is 6ppm
You want to maintain the target or above, not just the minimum so u don’t risk falling below minimum incase of high uv, high bather load, or other environmental factors FC/CYA Levels

Running that unit @50% 24/7 should yield around 7.6 ppm/day in your pool
The average pool uses 2-4ppm/day (give or take depending upon the season & location)
U can use PoolMath effects of adding in the hamburger menu (top left) to mess with % & run times to get a better idea of what you need to do to make around 4ppm/day
Select swg instead of bleach & use the to find your unit on the list.
Enjoy your vacay!

 

[mchimes]

Target fc for 80ppm cya is 6ppm
You want to maintain the target or above, not just the minimum so u don’t risk falling below minimum incase of high uv, high bather load, or other environmental factors FC/CYA Levels

Running that unit @50% 24/7 should yield around 7.6 ppm/day in your pool
The average pool uses 2-4ppm/day (give or take depending upon the season & location)
U can use PoolMath effects of adding in the hamburger menu (top left) to mess with % & run times to get a better idea of what you need to do to make around 4ppm/day
Select swg instead of bleach & use the to find your unit on the list.
Enjoy your vacay!

Thanks for your help! That makes sense. I have read conflicting things and listened to a podcast with Bob Lowry that target FC for SWG is 5% because it is constantly being generated vs. being dumped once every few a days. So I should shoot for 7.5%? Florida sun and rain and I have a decent amount of tree debris. Thanks!

 

[PoolStored]

Thanks for your help! That makes sense. I have read conflicting things and listened to a podcast with Bob Lowry that target FC for SWG is 5% because it is constantly being generated vs. being dumped once every few a days. So I should shoot for 7.5%? Florida sun and rain and I have a decent amount of tree debris. Thanks!

If you are going to target 80 for your CYA, your target is 6. Having said that, your chlorine demand can be highly variable. My CYA is 80 and I usually keep my FC 8-10. I can have between 2.5 and 5.5FC demand days. Keeping it a bit higher, keeps me away from minimums if I have a high demand day.

Also, when I'm on vacation, I know the setting that will raise my FC somewhere between .25 and .5 FC per day. When I leave for 5 days, my FC is about 1.5-2 higher than when I left.