Long SLAM, 17 Days & Counting

[Caracat]

This thread is a combined thread from three previous threads. There may be some jumping around but the need to combine these threads to reduce confusion was necessary! Thanks - Marty - TFP Mod


The good news: We've gone from pic A to pic B since Sunday!
Started SLAM w/ ph at 7.2, CYA 55, shocking to FC 24. Day one hourly, Day 2, every hour & a half, day 3 & 4 every 2 hours.
Water temp 85, Air temp high 80s
Total FC losses:
Day 1 39.5 (started SLAM late, at 3:30 PM)
overnight loss 8
Day 2 31 FC lost over 12.5 hours
overnight loss 4.5
Day 3 30.5 FC lost over 12.5 hours
overnight loss 5 (with all toys, poles & brushes soaking in pool overnight)
Day 4- current, 3 FC lost in 2.5 hours so far
At this rate I'll be on my 20th jug of chlorine by sundown.

Questions:

1) Is it normal to still be losing this much chlorine at this stage? The water is crystal clear and blue. It looks GREAT, but the chlorine smell is pretty overwhelming.

2) I have scrubbed the heck out of the entire pool, every crevice, nook and cranny, skimmer, baskets, weir, etc. with a steel wire brush, EXCEPT the light fixture. I can't get the screw to turn to save my life. It's rusted in place and stripped. The light is quite loose, I could cut off the head with bolt cutters, but I don't know how I'd get the rusty remainder out if I did. There is no power to the light. (Ideas welcome!)

Thanks, y'all!
Cara

 

[Texas Splash]

Re: Long SLAM, 17 Days & Counting

Nice progress! The chlorine smell might be more indicative of combined chlorines being released and not simply the fresh chlorine being added. Are you chlorinating with regular bleach or are you using anything else? Have any other products been added to the water in the past that you know of? You seem to be watching the FC consumption closely which is great. What about the filter? Have you opened that up yet? Do you notice any changes in pressure over time?

As for the light, at some point you'll have to get in there, even if you have to cut the head off to gain access and set the light on the decking for a while. You might have to drill it out or use a tap/extractor. We can come back to that a bit later if it comes to it, but t does sound like you'll want to look back behind that light and clean that area out.

 

[Caracat]

Re: Long SLAM, 17 Days & Counting

Oh yes, I've added so much junk to this poor pool. It's our first, and we just moved here about a year ago. Everything Leslie's told me try plus various junk from Amazon. Clarifiers, copper-based algaecides, weekly maintenance products, phosphate removers, boatloads of cal-hypo shock, compressed chlorine tablets. Three different pool companies have come out and done further damage, adding who knows what. You name it. I've done it wrong! I also have an 11-year-old boy, so add four or five oil drums worth of urine to all that. Then I found TFP and got a good test kit.

I found that my CYA level was 120 my CH was 525. So, before beginning to SLAM I exchanged half the water. We are now down to 55 CYA and 275 CH. Much better!

I'm using 12.5% bleach (no additives!) from Leslie's for now. It was produced in late August of this year, so pretty fresh. It's great to know that the smell might indicate getting rid of the bad. I backwashed yesterday, although my filter pressure hasn't increased at all since I started to SLAM. I have not taken apart and cleaned the filter in about 2 months. That's a question I meant to ask, but forgot about. Do you clean it during the SLAM or after it's complete? And when I clean the cartridges can I just hose them down, or do I need to soak them in something to kill algae?

My husband is going to take a crack at the light this evening. I know I need to get behind there or I could just be wasting all this time and $ for nothing!

Thank you!

 

[jblizzle]

Re: Long SLAM, 17 Days & Counting

You should clean the filter whenever the pressure rises 20-25% over the clean pressure.
Any organics captured in the filter will continue to consume chlorine as they are broken down.

Also note that the higher the FC is over the "normal" levels for your CYA, like you are for the SLAM process, the more ppm of FC that will be lost to the sun each day. So, unfortunately, there will continue to be large FC losses to the sun even if most of the stuff in the water is eradicated.

 

[Texas Splash]

Re: Long SLAM, 17 Days & Counting

I don't know how much Leslie's is charging, but you might also compare the price of Leslie's 12% liquid chlorine to regular bleach like HEB's regular Bravo where one gallon of 8.25% is about $2.94. Of course with the stronger 12% you should need less, but sometimes the cost doesn't add up. Just figured I'd mention that if it helps save a few bucks. Good thing you exchanged some water. It does sound as though the chlorine is working on trying to eliminate the many by-products in the water.

You mentioned cleaning the cartridges which makes us think of a regular (pleated) cartridge filter, but your signature shows a DE filter (w/ grids/fingers/manifolds). Can you confirm which you have? Thanks.

 

[Caracat]

Re: Long SLAM, 17 Days & Counting

Thanks for the note on the HEB brand bleach! Leslie's 12.5% works out to $4.74 per gallon. (Now to figure out the math!)
I probably used the wrong wording. By, "filter" I meant the 4 grids in my Quad DE system. How would you recommend cleaning them post SLAM?

 

[jblizzle]

Re: Long SLAM, 17 Days & Counting

Price / (oz * %)

Leslies: 4.74 / (128 * .125) = $0.296 / oz chlorine
HEB: 2.94 / (121 * 0.0825) = $0.295 / oz chlorine ... assumes the bottle is not really a gallon is is 121 oz like most of the 8.25% ... this is only slightly cheaper.

Neither are all that great of a price.

 

[Texas Splash]

Re: Long SLAM, 17 Days & Counting

We have a couple really good threads out there about DE filters. Here are a couple that should help:
Use and care for DE filters
DE Filter Cleaning Tutorial

Now 4 days isn't too long for a SLAM. A SLAM can take a good week or two. Just depends on how bad the water was. In your case though, with a bit of unknown history behind the pool and filter, you might find that after a week if you don't see the FC usage drop, you might elect to do a good inspection/cleaning of the filter. Backwashes are fine in most cases, but with all the oils and stuff added in the past, there could be more to the story inside. You can play that by ear over the next couple days. Maybe the light and filter would be a good weekend thing .... IF the weather cooperates.

 

[Caracat]

Re: Long SLAM, 17 Days & Counting

Thanks, those filter tutorials are AWESOME! I will clean ours tomorrow while hubs smokes a brisket and works on getting that dang light out. Day 4 total FC losses were 24, and yesterday (day 5) we lost 16.5. It looks like we are headed in the right direction. In reading the links you sent I noticed a lot of people saying they hardly ever backwash, if at all. We were told to backwash bi-weekly during the winter and every week during the summer, regardless of pressure changes! We never really did it that often, as we hated to use that much DE. We were also told to do the full breakdown and filter cleaning every 3 months. What is the REAL recommendation for backwashing and filter cleaning frequency, given that we are in the very hot South, get a lot of pollen in April/May and various types of leaves, bugs, flowers & other debris pretty much year round?

 

[mknauss]

Re: Long SLAM, 17 Days & Counting

Clean your filter (backwash) when the filter pressure rises by 25% over the clean filter pressure.

A full breakdown once per year. You may be able to go an entire year without backwash and just do the full breakdown.

 

[Caracat]

Re: Long SLAM, 17 Days & Counting

Day Twelve. The SLAM continues.

On day one I lost 39.5 PPM FC during the day in just 6 hours. I lost another 8 PPM that night.
Yesterday (day eleven) I lost only 8.5 PPM during the day (12 hours) and 3.5 overnight.
I've gone from adding chlorine every hour to about every 4 hours, keeping the FC at shock level 24 for my CYA of 55.

Started SLAM w/ PH 7.2.
I haven't turned off the pump.
Have brushed and brushed and brushed.
Backwashed once. Have not completely disassembled & cleaned the filter, as I just did that two months ago.
No pressure increases. Water has been crystal clear and blue since day 3.

I'm a little confused about when to let my chlorine levels taper down to what is more normal (about 9) for my CYA. Must I remain at shock level continually until that magical night when my FC losses are finally less than 1 PPM? Is there any danger to my equipment in keeping the FC at 24 for nearly two weeks straight now? In reading other SLAM posts it sounds like mine is taking a lot longer than what is normal, even for pools that started off in far worse condition.

I just got a $253 water bill yesterday (had to exchange half my water to get CYA down) and have spent over $200 on chlorine & testing chemicals. I need to be sure I'm not using ANY more chlorine than I absolutely have to. (We want to keep eating!)

Thanks! You guys are the best.
Cara

 

[Catanzaro]

Re: Long SLAM, 17 Days & Counting

Cara:

Can you provide a more detailed timeline over the last 12 days? Is it all possible you had ammonia in the first day or so? What does your water look like? Stop adding chlorine, wait 24 hours and determine how much you lost? Something does not add up. Unless you have algae lurking everywhere and can not see it. Please upload some pictures of the pool and water? What about combined chlorine results?

 

[Caracat]

Re: Long SLAM, 17 Days & Counting

Ammonia? Maybe. Why not? We bought the house/pool and moved in a couple days before Halloween 2017, so we don't know much of it's history. (Built in "61, so LOTS of history!) We also had hurricane Harvey in late August/early Sept 2017- right before we got here. There was tons of flooding nearby, though this house did not flood, but any number of contaminants could have been introduced into the water. Sewer breaks were everywhere. We started having big algae problems in April of this year after no real issues from Oct-March.

The algae never went away despite the, "help" of 3 different pool companies, hundreds of $ at Leslie's and on Amazon trying to solve our issues with chemicals. I had surgery and was on bed rest for 2 months this summer, so I could not do a lot of physical stuff to it

I finally found TFP in Sept and got a proper test kit. Our CH levels were high (525) but the main problem was our CYA, about 120. Any chlorine we added disappeared almost overnight. We were using Cal-Hypo shock and CYA-loaded pucks.

In April the algae was green and easy to scrub, even with just a finger. It turned more yellow later, impossible to scrub. (Steel bristles only, circular motion) We have disassembled and cleaned DE quad filters 3 times- April, June & August. I can't upload any more pictures because apparently I've hit a limit with photos in a few previous posts. The pool looks amazing, beautiful, perfect, inviting. It's been clear as a bell since day 3 of SLAM.

It was always clear, but we started SLAM with a green tinge and some algae spots. There are no more spots and the pool is gorgeous blue. We did find some grossness behind our pool light, a lot of it. It's all been scrubbed and vacuumed thoroughly. Still stained, but those stains aren't coming out, so I think they are permanent.

We are slowly losing less FC during the day and overnight. But it just seems ridiculously slow at this point, especially since we started SLAM with temps in the low 90s for high, 70s low, and are now down to highs in the 70s, 50s at night.

Grateful for any ideas you have!

 

[Catanzaro]

Re: Long SLAM, 17 Days & Counting

Grateful for any ideas you have!

Thank you for some more detailed information. What I was asking is a history of the last 12 days. When you tested, when you added chlorine, how much you added each day, how much you lost each day, etc.? A timeline tells a story. When you look at it in sequence, things come out at you and it is easier to figure out what is really going on. As mentioned before, test at around 9 p.m. this evening and do not add anything. Your levels should be at 10 or greater. Now, go through the day and do not add anything and lets determine how much you lose in a 24 hour period. It is highly suggested that you use the Taylor K-1000 to check for the presence of chlorine every 2 hours or so. The tube color should be bright yellow and remain there. If you are losing more than 5-6 in a 24 hour period, then clearly there is something still lurking in the pool.

With detailed information and the TF-100 test kit, there should be absolutely no reason why you can not get to the bottom of this problem. Also, to confirm you have not been adding anything else beside chlorine? No magic potions, no algaecides, etc.?

 

[DuaeGuttae]

Re: Long SLAM, 17 Days & Counting

I’m no TFP expert. I bought a house with a pool about the same time you did and have been learning a lot from this website. If what I’m going to say is wrong, it will be corrected, but you might want to try letting your chlorine drift down from your Shock level that you’ve been maintaining for another OCLT. The guide above suggested 10, but I thought it might have been not have been clear that you might be seeing greater losses because you are testing at high levels. There is a margin of error in the testing, and it increases the more drops you add. I see that you have the Speedstir, so that helps a lot. Try to be really precise in getting your 10 ml water sample each time, and it’s better to overshoot the powder than undershoot it.

Do you have natural rocks by your waterline where algae might lurk? We have a crack beside our spa spillover where water seeps, and algae grows. It’s not in the water for regular chlorination, but I figure that it’s a place I need to watch along with where water laps at the porous rocks on our waterfall.

I read your other threads, and it sounds like you have a good handle on the concepts and have been working hard. It is kind of overwhelming learning all this pool stuff, but this site will definitely help you understand your chemistry and manage it effectively.

 

[Caracat]

Re: Long SLAM, 17 Days & Counting

What I was asking is a history of the last 12 days.

Also, to confirm you have not been adding anything else beside chlorine? No magic potions, no algaecides, etc.?

Okay, this is long! But maybe you can see a pattern:

Oct 7 (High 91, Low 77)
3:34 CYA 55 Ph 7.2, FC 0, CC.5 +4 gals 10% added to raise FC to 17
4:04 FC 3.5, CC .5 +3 gal, 1 qt to FC 17
5:22 FC 10.5 CC .5, +2 qt, 2 c to FC 17
6:40 FC 13, +1 gal 1 c to FC 24
(after TFP forum experts recommended a higher shock level of 24, & said don't bother testing CC right now)
7:52 FC 16, +3qt, 1 c to FC 24
9:03 FC 16.5, +3qt to FC 24
Total daytime loss: 39.5 CC

Oct 8 (Hi 90 Lo 77)
8:16 16 FC, +3qt to FC 24 (8 FC overnight loss)
10:00 16 FC, +3qt to 24
11:38 19 FC, +1 qt, 3c to 24
1:44 19.5 FC, +1qt, 3c to 24 (Pressure 14, w/ Vac on)
3:00 20 FC, +1qt, 2c to 24 (Pressure 20, No vac)
4:45 20 FC, +1qt 10%, +1c, 6oz 12.5% (used only 12.5% from this point forward) (P 20, No V)
6:43 21.5 FC, +3c, 1oz to 24 (P 20, No Vac)
8:50 21 FC, +3c, 6oz to 24 (P 20, no vac)
Total daytime losses 31 FC (P 20 no vac)

Oct 9 (91/73)
7:44 19.5 FC, +1qt, 1 c, 5oz to 24 (4.5 FC overnight loss) (P 20, no vac)
9:45 20 FC, +1qt, 1 c to 24 (P 20, no vac)
11:47 21 FC +3c, 6oz to 24 (P 13, w/ Vac)
2:20 17.5 FC +2qt, 1oz to 24 *After swimming & brushing walls, floor, skimmer, steps, etc with steel brush under water for couple hours
4:20 18FC +1qt, 3c, 4 oz (P 13 w/ vac) *backwashed!
6:31 18 FC +1qt, 3c, 4zo (P 12 w/ vac)
8:18 19 FC, +1qt 2c, (P 18, no vac)
Total Daily losses 30.5

From this point forward I'll just put time, FC level, filter pressure, total daily losses and special notes. I added chlorine to reach 24 after each reading:

Oct 10 (86/72)
7:50 19 FC, 18 No Vac (5 overnight loss)
10:22 21 FC, 10 w/ Vac
12:22 19 FC, 10 w/ vac *water low, put hose in pool for couple of hours
3:00 17 FC, 19.5 no vac
5:00 20 FC
8:20 19 FC
Total daytime losses: 24

Oct 11 (82/66)
7:59 19 FC, 18 no vac (5 overnight loss)
11:33 20 FC, 18 no vac
4:42 17.5 FC, 18 no vac
8:24 18 FC
Total day losses: 16.5

Oct 12 (88/66)
7:50 20 FC, 18 no vac (4.0 overnight loss)
10:15 21 FC *ran out of chlorine, so added more about an hour later
2:48 too low on R-0871 to test, added 1 qt 3 c total guess
8:00 17 FC, 10 w/ vac
Total daily losses unknown due to issues above

Oct 13 (90/75)
8:14 18FC (6 overnight loss)
*Approx noon- Hubs got the stuck pool light out & it was GROSS behind there. Scrubbed out thoroughly, vacuumed
4:27 15FC
10:05 17.5 FC
Total daily losses: 15.5

Oct 14 (93/77)
8:15 16FC (8 overnight loss)
10:01 20.5 FC
12:40 19.5 FC
5:20 19.0 FC, 18 no vac
8:11 18.5 FC
Total daytime loss 18.5

Oct 15 (79/57) *sudden temp drop
8:08 18.5 (5.5 overnight loss)
2:58 16.5, 11 w/ vac
8:29 16.5
Total day loss 20.5

Oct 16 (63/55) *much cooler
8:10 19FC (5.0 overnight loss)
2:47 20FC, 11 w/ vac
8:22 19 FC
Total day loss 9

Oct 17 (64/55) *much cooler
8:06 20FC, 11 w/ vac (4.0 overnight loss)
2:20 19.5FC
8:11 20 FC
Total day losses 8.5

Oct 18 (72/57) *much cooler
8:09 20.5FC, 11 w/ vac (3.5 overnight loss)
12:26 21FC
8:05 19.5FC
Total Day loss 7.5

Oct 19 (81/68)
7:25 20, 11 w/ vac, (4 overnight loss)

I have added algaecides, phosphate removers & clarifiers in the past. (everything I shouldn't have!)
I've added only liquid chlorine since I found TFP 4-6 weeks ago. I drained half that old water and refilled prior to SLAM, so I did use a little muriatic acid to get Ph right before SLAM. Otherwise, NOTHING else added recently.

 

[Catanzaro]

Re: Long SLAM, 17 Days & Counting

I see a progress, meaning that whatever is lurking in your pool is slowly disappearing. Never use clarifiers, especially if you have a DE filter. Algaecides only work when there is no algae. Phosphate Removers are fine if you use yearly or twice a year at most (assuming your phosphates are high), but still may not be necessary.

I do not have a DE filter, but have you cleaned out the filter grids? What is strange is that you only have had to backwash once (really no pressure rise), but are consuming a tremendous amount of bleach. Where exactly are you purchasing the bleach? What is the time stamp? Are you sure your pool is 24,000 gallons, or could it at all be larger?

You really should be down to less than 4 ppm daily over the next few days. If not, then either something is going on with your filter, your pool volume is larger, or the bleach is not fresh.

Before I knew about bleach degradation and the Julian date, I purchased 9 month old 12.5%. We realized that I was consuming more than necessary, not because I had issues with my pool, but the bleach. Thanks!

 

[Caracat]

Re: Long SLAM, 17 Days & Counting

try letting your chlorine drift down from your Shock level that you’ve been maintaining for another OCLT. The guide above suggested 10, but I thought it might have been not have been clear that you might be seeing greater losses because you are testing at high levels. Try to be really precise in getting your 10 ml water sample each time, and it’s better to overshoot the powder than undershoot it.

Do you have natural rocks by your waterline where algae might lurk?
.

Thanks! Would LOVE to drop down to 10! Staying at 24 'til a few people can look over my daily SLAM records. I am going to go ahead and call myself ridiculously precise. I always rinse and dry everything, test within a minute of taking water sample, test indoors only, super bright light, wearing glasses, at eye level. Sometimes I even take samples from 3-4 different parts of the pool and test them one right after the other just for the heck of it. I'm an overkill tester, and probably an overkill chlorinator!

Nope, pool was built in 1961. Absolutely no rocks or special features, No spa. The only area I just can't be sure about is the light recess. It's been scrubbed and scrubbed, but it still looks pretty awful.

 

[Caracat]

Re: Long SLAM, 17 Days & Counting

have you cleaned out the filter grids? What is strange is that you only have had to backwash once (really no pressure rise), but are consuming a tremendous amount of bleach. Where exactly are you purchasing the bleach? What is the time stamp? Are you sure your pool is 24,000 gallons, or could it at all be larger?

You really should be down to less than 4 ppm daily over the next few days. If not, then either something is going on with your filter, your pool volume is larger, or the bleach is not fresh.

I have not broken down and done a heavy filter cleaning because I did one a couple of months ago, but I'm planning to go ahead with one this afternoon or tomorrow. Seems like the only thing left do do at this point. Been getting bleach from Leslie's. Julian date is late August. They store it indoors. Was getting at Lowes before for slightly cheaper, but they keep it outside in the heat and I was worried about potency. I am pretty sure our pool size is correct. I calculated it myself once and got pretty much the same number the previous owners gave us.

 

[DuaeGuttae]

Re: Long SLAM, 17 Days & Counting

Thanks! Would LOVE to drop down to 10! Staying at 24 'til a few people can look over my daily SLAM records. I am going to go ahead and call myself ridiculously precise. I always rinse and dry everything, test within a minute of taking water sample, test indoors only, super bright light, wearing glasses, at eye level. Sometimes I even take samples from 3-4 different parts of the pool and test them one right after the other just for the heck of it. I'm an overkill tester, and probably an overkill chlorinator!

Nope, pool was built in 1961. Absolutely no rocks or special features, No spa. The only area I just can't be sure about is the light recess. It's been scrubbed and scrubbed, but it still looks pretty awful.

When I mentioned “testing error,” I’m sorry if it sounded as though I was saying you weren’t doing the tests properly. I was really referring to Taylor’s own acknowledged variance in test readings. I think it’s something like 10%, though I don’t recall exactly.

Do do you have a main drain in the pool where organics could be lurking out of sight? I’m just trying to think of some sources of contamination I’ve read about with other surprisingly long SLAMs.