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Thread: The neverending SLAM - am I missing anything?

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    The neverending SLAM - am I missing anything?

    Hi folks.

    I've been engaged in a SLAM since Friday June 17, and it shows no sign of ending.

    I've made other posts, and some of you have been helping me out which I really appreciate. I'll try to consolidate all the relevant information here including the latest developments.

    When I started the SLAM, there was no visible algae, and the water was crystal clear. The only reason for embarking on the SLAM was that I had just taken over maintenance of the pool and the free chlorine level was not holding.

    My initial numbers on June 17, 2016 were:

    FC 0.4
    CC 2.0
    pH 7.1
    TA 100
    CH 500
    CYA 30

    For the rest of this post, I'll post FC and CC numbers only. I was told that the pH test is not accurate at elevated chlorine levels. I did test pH a couple times during the SLAM and it seemed to indicate around 7.0. (Slightly beyond the color scale.) TA and CH I did not test during the SLAM (and probably aren't relevant). CYA I tested on June 19 and June 25 and both times confirmed it was still at 30.

    I have many measurements during the SLAM as I tried to keep the FC levels up, but I'm going to just give you the OCLT numbers.

    Date Time FC CC
    2016-06-17 23:00 9 1.5
    2016-06-18 09:30 0.5 1
    2016-06-18 21:45 10 1
    2016-06-19 02:15 6 1
    2016-06-20 01:00 11 1
    2016-06-20 07:00 7.5 0.5
    2016-06-20 22:45 15 1
    2016-06-21 06:30 9.5 0.5
    2016-06-21 23:15 8 0.5
    2016-06-22 07:00 6 0.5
    2016-06-22 22:30 9.5 0.5
    2016-06-23 06:45 6.5 0.5
    2016-06-23 21:15 9.5 0.5
    2016-06-24 06:45 6 0
    2016-06-24 22:00 15 1
    2016-06-25 09:15 8.5 0.5
    2016-06-25 22:30 13 0.5
    2016-06-26 10:15 7.5 0.5
    2016-06-26 23:15 13 0.5
    2016-06-27 07:00 8 0.5



    You can see that during the week I did not keep up the proper SLAM levels overnight b/c I knew I wasn't able to tend to the pool properly during the week, but during the weekend I embarked on it again wholeheartedly.

    I did not have a brush when I started the SLAM, but I ordered one since then. But once again, there is no visible algae.

    The inside of the skimmer looks clean. (Aside from the usual collection of leaves and bugs which I clean out daily.) At first, I thought the input well was filthy, but after I drained and cleaned it out, it turned out that it just looked bad b/c the well wall was black and made the water look dark. As I took the water out, it was mostly clear, and there was only a little sediment at the bottom. There are no ladders in the pool for algae to collect on, and the built in stairs look clean (but I have brushed them anyway).

    One thing that got my hopes up for the cause was the in-pool light. I removed it on June 25 (so well into the SLAM), and when I did so, a bunch of debris flew out of the alcove -- pretty disgusting. I scooped out what I could and the rest I broke apart with the brush at the bottom of the pool so that eventually it should filter out.

    Other than that, the only other thing I can think of is that the filter is dirty. I meant to clean it last weekend but did not get the chance. But my understanding that even if the filter is dirty, algae can't grow in there since there is no light. True or not?

    So at this point, I've been sort of SLAMing for over a week. I know that I'll get told that I haven't been properly SLAMing since I did not keep SLAM levels up the entire time (during Monday through Friday of last week). That is true, and I fully admit that. But I have been keeping elevated levels (if not SLAM levels) so that it should at least have been prohibiting additional growth.

    Since the beginning of the SLAM, I have added over 40 jugs of chlorine (1 gallon of either 8.25% or 10% bleach), so I'm kind of discouraged. It feels like the SLAM will never end. I think the advice people will give is to just keep at it. But doesn't it seem like things should have stabilized by now? My pool has looked great since the beginning of the SLAM. But clearly something is going on to cause the FC level to drop so much overnight. Is there a point at which I'm just going to stop? I don't want to if there's something consuming chlorine, but I feel like no progress is being made. I do feel like progress was being made in the beginning where a lot of CC was being produced and my chlorine demand was higher than it is now. But I don't feel like I'm making progress now.

    Other than cleaning out the filter, what else can I do now? Are there any other "hidden" sources of algae or organics you can think of?

    Thank you for all your help! You guys have been terrific in supporting me!

    Mason
    25,000 gallon plaster pool, Pentair IntelliFlo VS+ SVRS pump, Sta-Rite System 3 Modular Media Filter Model S7M120 (cartridge), Aqua Ultraviolet UV Sterilizer (not used), Polaris 380 w/ booster pump, Taylor K-2006 test kit

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    Mr Bruce's Avatar
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    Re: The neverending SLAM - am I missing anything?

    Seems pretty straightforward. Slam level for 30 CYA is 12. It was only brought to 12 a couple of times. Between that and algae behind the light until day before yesterday no big mystery.

    I bet if you were to get to slam level 3-4 times per day for the rest of the week you might be done by Friday.
    32K gallon Plaster - 1hp Hayward 2 speed Super Pump - Hayward S200 Sand Filter - TF100XL
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    Re: The neverending SLAM - am I missing anything?

    Okay Mason, now you must go over to the chalkboard and write 100 times, "I will maintain my TFP SLAM FC Level".

    You summed it all up here:
    I know that I'll get told that I haven't been properly SLAMing since I did not keep SLAM levels up the entire time (during Monday through Friday of last week). That is true, and I fully admit that. But I have been keeping elevated levels (if not SLAM levels) so that it should at least have been prohibiting additional growth.
    That's what is hurting you and stalling your progress. In addition, as you already noted, you're costing yourself more bleach in the long-run by dragging it out and not maintaining the SLAM FC level. You must maintain and do all the things on the SLAM page for it to be effective. There simply is no other way around it.

    Pat (a.k.a. Texas Splash) ~ My Pool: Viking Fiberglass; 17,888 Gal; Waterway Supreme 2-sp/2-hp pump; Hayward Ctg filter; TF-100 w/ Speed Stir
    Vital Links: POOL SCHOOL, RECOMMENDED LEVELS, RECOMMENDED CHEMICALS, Poolmath Calculator, SLAM, Chlorine/CYA CHART.
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    Re: The neverending SLAM - am I missing anything?

    Let me clarify: the numbers I provided were only the overnight numbers so you could see the progress of the OCLT. During the day I raised it up to SLAM level as often as I could. Over both weekends, I definitely brought it up to SLAM levels more than once per day.

    Mason
    25,000 gallon plaster pool, Pentair IntelliFlo VS+ SVRS pump, Sta-Rite System 3 Modular Media Filter Model S7M120 (cartridge), Aqua Ultraviolet UV Sterilizer (not used), Polaris 380 w/ booster pump, Taylor K-2006 test kit

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    Re: The neverending SLAM - am I missing anything?

    Did you leave the light out of the alcove so that the alcove could receive constantly refreshing chlorinated water?
    8,500gal plaster in-ground with attached spa, two floor drains, one skimmer. Chlorine, City Water.
    Pentair WhisperFlo 1hp Pump, MagnaTek Midcentury EPlus motor, Pentair CleanNClear 200SF Cartridge filter, Purex Triton MiniMax 250 Gas Heater, Pentair SunLite, AutoFill.
    Kreepy Krauly Cruiser, TF-100 with SpeedStir. :D

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    Re: The neverending SLAM - am I missing anything?

    That's understandable. Many TFP'ers have difficult work schedules and such that make it tough to watch the pool. But the more the FC drops below the SLAM (12 in your case) the longer the SLAM will take. Even many of the OCLT late-night tests your recorded were below the FC of 12, so I suspect all of those FC drops are still hurting you.
    Pat (a.k.a. Texas Splash) ~ My Pool: Viking Fiberglass; 17,888 Gal; Waterway Supreme 2-sp/2-hp pump; Hayward Ctg filter; TF-100 w/ Speed Stir
    Vital Links: POOL SCHOOL, RECOMMENDED LEVELS, RECOMMENDED CHEMICALS, Poolmath Calculator, SLAM, Chlorine/CYA CHART.
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    Re: The neverending SLAM - am I missing anything?

    Quote Originally Posted by triptyx View Post
    Did you leave the light out of the alcove so that the alcove could receive constantly refreshing chlorinated water?
    Yup, it's still out. I also brushed out the alcove the best I could with the pool brush. I'm not going to put the light back in until I can actually get in the pool and visually inspect the alcove. (Too difficult from above-pool level.)

    Thanks!
    25,000 gallon plaster pool, Pentair IntelliFlo VS+ SVRS pump, Sta-Rite System 3 Modular Media Filter Model S7M120 (cartridge), Aqua Ultraviolet UV Sterilizer (not used), Polaris 380 w/ booster pump, Taylor K-2006 test kit

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    Re: The neverending SLAM - am I missing anything?

    Quote Originally Posted by Texas Splash View Post
    That's understandable. Many TFP'ers have difficult work schedules and such that make it tough to watch the pool. But the more the FC drops below the SLAM (12 in your case) the longer the SLAM will take. Even many of the OCLT late-night tests your recorded were below the FC of 12, so I suspect all of those FC drops are still hurting you.
    Yes.

    The first weekend, I was unfortunately away for long periods of time.

    The second weekend, I was able to stay closer and keep the levels up better.

    Okay, so here's a question. People have often asked (numbers stated for my CYA level), "If 12 is good, then is 15 even better?" And the response is, "No, going higher is not more beneficial." That's totally fair. But if I have trouble staying close to the pool, perhaps 15 *is* better. It's not worse than 12. So if I raise it to 15 before I go to work, at least it can stay a higher level during the day. True? And yet I've not heard anyone advise that.

    Also, while I will endeavor to keep the FC level up (honestly, I'm trying), it's also true that while 8 is not 12, 8 is also not 2. It's not like 12 is some magic number where at 12 it's working and below 12 it's not.

    So I swear I will try to keep the levels up as best I can, but I should be seeing progress, shouldn't I? Do you really feel like this pattern is explained by just persistent algae growth? Or do you suspect that I am in fact missing something and there's some problem that I need to address other than just keeping my FC levels up? (Do you think the filter could be a culprit?)

    Thanks for your help!!

    Mason

    - - - Updated - - -

    Quote Originally Posted by SongMonk View Post
    Yup, it's still out. I also brushed out the alcove the best I could with the pool brush. I'm not going to put the light back in until I can actually get in the pool and visually inspect the alcove. (Too difficult from above-pool level.)

    Thanks!
    Now that I think about it, I probably should let the light dangle in the pool in case there is any growth on the light itself. Or would that be too hard on the cord?

    Actually, probably any algae growth will die on the light being out of the pool too since it will be dry and exposed to sunlight. Right?

    Mason
    25,000 gallon plaster pool, Pentair IntelliFlo VS+ SVRS pump, Sta-Rite System 3 Modular Media Filter Model S7M120 (cartridge), Aqua Ultraviolet UV Sterilizer (not used), Polaris 380 w/ booster pump, Taylor K-2006 test kit

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    Texas Splash's Avatar
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    Re: The neverending SLAM - am I missing anything?

    But if I have trouble staying close to the pool, perhaps 15 *is* better. It's not worse than 12.
    This was discussed before and the TFP panel agreed that increasing over & above the SLAM number is not the best advice for us to give. It doesn't mean YOU can't do it, but we (TFP) won't recommend it for various reasons. Things like damaged liners, unpredictable/unknown FC increases, waste of FC to oxidation, etc. There were just too many unknown variables, so we agreed that sticking to the SLAM guidance is what we will do at TFP. If someone is at work all day, then they'll just have to increase it back up once they get home.

    Should the FC increase (even if below SLAM) help and show some improvement? You would think so, but only to a point. Each pool is different (amount of algae, consistency of FC, amount of sunlight, etc) so slipping a few ppm under the SLAM FC may not be as detrimental to one pool as the one next door. But overall, the Chlorine/CYA Chart was developed after much consideration to many of the things you've commented on. Following the chart provides the optimal ratio of FC and CYA to combat algae while protecting equipment.
    Pat (a.k.a. Texas Splash) ~ My Pool: Viking Fiberglass; 17,888 Gal; Waterway Supreme 2-sp/2-hp pump; Hayward Ctg filter; TF-100 w/ Speed Stir
    Vital Links: POOL SCHOOL, RECOMMENDED LEVELS, RECOMMENDED CHEMICALS, Poolmath Calculator, SLAM, Chlorine/CYA CHART.
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    Re: The neverending SLAM - am I missing anything?

    I don't see anything wrong with raising FC higher so that you don't fall below 12. Mustard shock level is 18 ppm. You could dose up to 18.
    27,500 gallon in ground gunite/plaster (1995). Attached Spa with fountain, spillway, and 2 lion heads streaming into the pool. Hayward pump and AO Smith UST1152 1.5 hp motor (single speed). Hayward 60 sq ft DE Filter (Model DE-6000). Kreepy Krauly cleaner.

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    Texas Splash's Avatar
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    Re: The neverending SLAM - am I missing anything?

    I don't see anything wrong with raising FC higher so that you don't fall below 12. Mustard shock level is 18 ppm. You could dose up to 18.
    True, but remember that's only advised for a 24 hour period to give MA a knockout punch. It's not recommended for 24/7 SLAM levels. Remember our SLAM levels take into consideration all pool types, so even though a plaster owner may be fine with increasing FC, it could be quite bad for a vinyl owner. Plus, FC oxidizes much faster above the target zone because there's not as much CYA to bind to, so the extra FC is an easy target to the sun. When it comes to a SLAM, "consistency" has proven to be better than inconsistent spikes and falls in FC.
    Pat (a.k.a. Texas Splash) ~ My Pool: Viking Fiberglass; 17,888 Gal; Waterway Supreme 2-sp/2-hp pump; Hayward Ctg filter; TF-100 w/ Speed Stir
    Vital Links: POOL SCHOOL, RECOMMENDED LEVELS, RECOMMENDED CHEMICALS, Poolmath Calculator, SLAM, Chlorine/CYA CHART.
    If you enjoyed your TFP experience, please consider donating to Support TFP!

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    Re: The neverending SLAM - am I missing anything?

    Thank you, Texas Splash. I appreciate what you are saying. I will keep at it.

    Mason
    25,000 gallon plaster pool, Pentair IntelliFlo VS+ SVRS pump, Sta-Rite System 3 Modular Media Filter Model S7M120 (cartridge), Aqua Ultraviolet UV Sterilizer (not used), Polaris 380 w/ booster pump, Taylor K-2006 test kit

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