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Thread: SLAM help please!!

  1. Back To Top    #1

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    SLAM help please!!

    Good morning all. The issue I have been dealing with is having to add 2-4 gallons(121 oz) of 8.25 bleach per day but passing the OFCLT until this past weekend when I did not pass so started the SLAM process. You can see the results below. My CYA was 40 when I started and this morning still appeared to be 40 so 16 is my shock number according to the chart, however it does not appear to be improving. This morning's loss was 3.4, yesterdays was 2.0. The FC numbers on the lines where bleach additions are made is a calculated number at +1.9 per gallon. This morning the CC was 0, TA -70, CH -300, PH - 7.9, CYA - 40.

    Wondering if I am reading my CYA number low and perhaps should bump up the shock number but not sure. Any suggestions would be much appreciated. Also the water is clear and beautiful, no visible signs of algae.

    Day Addition Time FC Overnight Loss

    Sunday 6:30 pm 4
    add 7 17.3
    9:00 pm 19
    add 0 19
    Monday 6:30 am 15 -4
    add 2 18.8
    2:00 pm 12
    add 3 17.7
    6:30 pm 11
    add 4 18.6
    9:00 pm 18
    add 0 18

    Tuesday 6:00 am 16 -2
    add 1 17.9
    1:30 pm 12
    add 3 17.7
    5:30 pm 13
    add 2 16.8
    9:00 pm 15.5
    add 1 17.4

    Wednesday 6:30 am 14 -3.4
    add 2 17.8
    Last edited by mbeck5; 07-08-2015 at 07:12 AM. Reason: additional information
    Mike

    Pool is inground 20' x 40' 42000 gallon, rectangular plaster about 60 years old, replastered 2 years ago. Pentair VS Intelliflo pump, Pentair 420 Clean & Clear Plus Cartridge filter. Using K-2006 test kit.

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    Texas Splash's Avatar
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    Re: SLAM help please!!

    Good morning Mike. Adding 2-4 gallons per day would appear excessive. If I'm following your notes above correctly, it looks like you have been trying diligently to keep your FC at/above 16 because you failed an OCLT correct? During this SLAM, have you been doing all the other SLAM requirements such as pump on 24/7, brushing the pool, checking any small niches/lights for algae access, cleaning the filter? If there's ANY algae hiding in those places, it will be noted on your tests. Losing more than 1 ppm on your OLCT does confirm you have organics somewhere eating your good chlorine, so you need to keep the SLAM going. During the day however, FC will go fast simply from the sun, so it's a constant battle.

    Next time when you post your test results, don't worry about PH since it's skewed during a SLAM, but continue to post for us the FC and CC. If you're sure the CYA is 40, no need to re-test each time either. It won't change that fast. Of course continue to post your OCLT each next morning. Let's see what other s have to say about your situation as well.
    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: SLAM help please!!

    Thanks for the response and you are correct. I had been using 2 - 4 gallons a day and passing the OCLT until the past weekend when I began the SLAM process Sunday night. Been cleaning the filters and brushing the pool daily but I cant tell you that I am 100% certain about the CYA test results. Checking separately, my wife and I agreed on 40 so that is the level I used. CC has been zero, no signs of algae, water is beautiful. Cartridge filters look dusty but no discoloration that I can detect. In the past before TFP had black, green and yellow algae but all has been great since I converted last year. Will keep on it and let you know the results tomorrow morning. Thanks again.
    Mike

    Pool is inground 20' x 40' 42000 gallon, rectangular plaster about 60 years old, replastered 2 years ago. Pentair VS Intelliflo pump, Pentair 420 Clean & Clear Plus Cartridge filter. Using K-2006 test kit.

  4. Back To Top    #4

    Re: SLAM help please!!

    Have you pulled out the light and the ladder?

    I have been slamming as well and the sun has been eating the FC up at midday. My water looked pretty darn good (clear but not sparkling clear) when I started with maybe a .5 cc. No visible algae either until I pulled the ladder that I had scrubbed twice and found some in the crannies under the rungs. It took me about 7 days to pass the OCLT. My water looked so good the last few days that I would have stopped slamming too early if it weren't for that test.

    Are you seeing any dead algae on the pool floor?
    18' x 36' saltwater inground vinyl pool

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    Re: SLAM help please!!

    Quote Originally Posted by ouachita View Post
    Have you pulled out the light and the ladder?

    I have been slamming as well and the sun has been eating the FC up at midday. My water looked pretty darn good (clear but not sparkling clear) when I started with maybe a .5 cc. No visible algae either until I pulled the ladder that I had scrubbed twice and found some in the crannies under the rungs. It took me about 7 days to pass the OCLT. My water looked so good the last few days that I would have stopped slamming too early if it weren't for that test.

    Are you seeing any dead algae on the pool floor?
    No lights and I pulled the ladder last year so not an issue. Havent seen any algae anywhere(walls, bottom, filter cartridges etc) so a little confusing. Prior to TFP we fought all kinds of algae without success but for the past year no problem. If it wasnt for the FC loss daily and failing the OCLT, I wouldnt suspect a problem. Cleaned everything again this morning and bumped up the FC to 20 so will see if it helps. Overcast today so that should slow the daytime loss but we will see. Will post again in the am and thanks for responding.
    Mike

    Pool is inground 20' x 40' 42000 gallon, rectangular plaster about 60 years old, replastered 2 years ago. Pentair VS Intelliflo pump, Pentair 420 Clean & Clear Plus Cartridge filter. Using K-2006 test kit.

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    Re: SLAM help please!!

    That's part of the beauty of this system is you can catch algae before you see it. The only algae I saw was the dead algae dust after I started shocking.
    18' x 36' saltwater inground vinyl pool

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    Re: SLAM help please!!

    How old are your test reagents?
    39YO 13K gallon former SWAMP/MONEY PIT, concrete bottom/Fiberglass Walls, Ecotech VS pump, Hayward Sand Filter, Dolphin DX5 Plus, Loop-Loc safety cover and YES, I have a TFT-100 test kit!

    Shock Level and Maintain - CL/CYA Chart

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    Re: SLAM help please!!

    Have you seen any increase in filter pressure since the start of the SLAM?

    Keep up the SLAM and it wont hurt it to have the FC a little over the SLAM target. The FC SLAM target is the value you want to not drop below during the SLAM.

    It most likely is a low level algae problem that hasn't been detected with the eye.
    16k gal plaster with raised spa, Jandy DEV60 filter, 2 HP 2-speed SHPF Jandy Stealth pump
    Hayward Aqua Rite T-15 SWCG, Jandy LXi 400k BTU NG heater, 350 sq.ft. of Sun Star solar panels, TF-100 Test Kit, Dolphin s300i Cleaner
    Test Kits . Pool Math . Chlorine/CYA Chart . The SLAM Process

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    Re: SLAM help please!!

    jaduck - 870 and 871 are 3 months old. More coming tomorrow just in case. Appreciate your asking. Just checked again and FC was down to 12 with no sun today and CC for the first time .5. Is it possible to have algae eat this much chlorine without being visible? Not many places for it to hide. Pool is a rectangle with no lights, just the inlets on one side and a bottom drain not being used. One skimmer attached to the first drain by the stairs, cleaned and checked okay.
    Mike

    Pool is inground 20' x 40' 42000 gallon, rectangular plaster about 60 years old, replastered 2 years ago. Pentair VS Intelliflo pump, Pentair 420 Clean & Clear Plus Cartridge filter. Using K-2006 test kit.

  10. Back To Top    #10

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    Re: SLAM help please!!

    Yes you can have algae without seeing visible evidence. I agree with ping, have you had a pressure increase on your filter?
    39YO 13K gallon former SWAMP/MONEY PIT, concrete bottom/Fiberglass Walls, Ecotech VS pump, Hayward Sand Filter, Dolphin DX5 Plus, Loop-Loc safety cover and YES, I have a TFT-100 test kit!

    Shock Level and Maintain - CL/CYA Chart

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    Re: SLAM help please!!

    ping - have not noticed an increase in pressure past what I would expect from filters getting dirty. Both cartridges were well under maximum this morning when i cleaned them and they registered a little below the minimum at start up and this has been normal for the past couple of years. Todays numbers are below. Seems incredible that the numbers would drop so much. My wife did not check the level at 11 but did add one more gallon and when I got home at 4, the level was 12 with a .5 CC(first time).

    Wednesday 6:30 am 14
    add 2 17.8
    8:00 am
    add 2 21.6
    11:00 am ?
    add 1
    4:00 pm 12
    add 4 19.6
    Mike

    Pool is inground 20' x 40' 42000 gallon, rectangular plaster about 60 years old, replastered 2 years ago. Pentair VS Intelliflo pump, Pentair 420 Clean & Clear Plus Cartridge filter. Using K-2006 test kit.

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    Re: SLAM help please!!

    Until advised by an expert I would just keep up the SLAM...not much else you can do.
    39YO 13K gallon former SWAMP/MONEY PIT, concrete bottom/Fiberglass Walls, Ecotech VS pump, Hayward Sand Filter, Dolphin DX5 Plus, Loop-Loc safety cover and YES, I have a TFT-100 test kit!

    Shock Level and Maintain - CL/CYA Chart

  13. Back To Top    #13

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    Re: SLAM help please!!

    Good morning. The loss last night was 1.4 so FC this morning was 15 and CC was 0. Since the OCLT results have varied will keep at it today. Also should receive a new chemical shipment today just to be sure. Water still looking great, pump pressure still low.

    Sunday 6:30 pm 4
    add 7 17.3
    9:00 pm 19
    add 0 19
    Monday 6:30 am 15 -4
    add 2 18.8
    2:00 pm 12
    add 3 17.7
    6:30 pm 11
    add 4 18.6
    9:00 pm 18
    add 0 18

    Tuesday 6:00 am 16 -2
    add 1 17.9
    1:30 pm 12
    add 3 17.7
    5:30 pm 13
    add 2 16.8
    9:00 pm 15.5
    add 1 17.4

    Wednesday 6:30 am 14 -3.4
    add 2 17.8
    8:00 am
    add 2 21.6
    11:00 am ?
    add 1
    4:00 pm 12
    add 4 19.6
    11:00 pm 14.5
    add 1 16.4
    6:45 am 15 -1.4
    add 2 18.8
    Mike

    Pool is inground 20' x 40' 42000 gallon, rectangular plaster about 60 years old, replastered 2 years ago. Pentair VS Intelliflo pump, Pentair 420 Clean & Clear Plus Cartridge filter. Using K-2006 test kit.

  14. Back To Top    #14

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    Re: SLAM help please!!

    Yes, a pool can look clean and take a while to complete a SLAM. The OCLT results say to keep on SLAMing and you are getting closer to the end. You need to remember only two things consume chlorine, sunlight and organics. The OCLT removes sunlight from the equation so you are left with organics as the culprit.
    16k gal plaster with raised spa, Jandy DEV60 filter, 2 HP 2-speed SHPF Jandy Stealth pump
    Hayward Aqua Rite T-15 SWCG, Jandy LXi 400k BTU NG heater, 350 sq.ft. of Sun Star solar panels, TF-100 Test Kit, Dolphin s300i Cleaner
    Test Kits . Pool Math . Chlorine/CYA Chart . The SLAM Process

  15. Back To Top    #15

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    Re: SLAM help please!!

    Pool is a rectangle with no lights, just the inlets on one side and a bottom drain not being used.
    Why isn't it being used?? Non functional??? Or just prefer not to use it???
    A possible source of your algae may be under the drain cap and/or in the piping. I know it may be a long shot, but there would be no circulation in the pipe if its not being used. No circulation would mean no chlorine is getting to it.
    Randy H.

    Intex 18' X 48"
    G.A.M.E. Sandpro 75 Sand Filter (Single Speed 3/4 HP, 75 lbs sand, 2650 GPH, 7-way valve)

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    Re: SLAM help please!!

    Quote Originally Posted by one_knight4u View Post
    Why isn't it being used?? Non functional??? Or just prefer not to use it???
    A possible source of your algae may be under the drain cap and/or in the piping. I know it may be a long shot, but there would be no circulation in the pipe if its not being used. No circulation would mean no chlorine is getting to it.
    It is functional but we were advised by a pool repair company replacing our pump that the bottom drain was not necessary and detracted from the skimmers so we stopped using it about 2 years ago. Wouldnt hurt to run it for a while if that is a possibility.
    Mike

    Pool is inground 20' x 40' 42000 gallon, rectangular plaster about 60 years old, replastered 2 years ago. Pentair VS Intelliflo pump, Pentair 420 Clean & Clear Plus Cartridge filter. Using K-2006 test kit.

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    Re: SLAM help please!!

    A main drain isn't necessary, but if you have one it needs to be used so chlorine is circulated there. All pool plumbing needs to be used unless it is permanently taken out.


    30K gallon IG vinyl. 1.5HP 2-speed Waterway Mustang pump. 600 lb sand filter. Polaris 280. Circupool SI-60+. TF-100

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    Re: SLAM help please!!

    Quote Originally Posted by n240sxguy View Post
    A main drain isn't necessary, but if you have one it needs to be used so chlorine is circulated there. All pool plumbing needs to be used unless it is permanently taken out.


    Sent from my iPhone using Tapatalk
    Opened it up this morning. Hopefully it will help with this issue but wondering why I was told it was okay to leave it off? What you are saying makes sense.
    Mike

    Pool is inground 20' x 40' 42000 gallon, rectangular plaster about 60 years old, replastered 2 years ago. Pentair VS Intelliflo pump, Pentair 420 Clean & Clear Plus Cartridge filter. Using K-2006 test kit.

  19. Back To Top    #19
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    Re: SLAM help please!!

    I have no idea why anyone would say it's ok to leave it there without using it. It'll just sit there with stagnant water in it, and algae can start to grow there since chlorine can't get to it.


    30K gallon IG vinyl. 1.5HP 2-speed Waterway Mustang pump. 600 lb sand filter. Polaris 280. Circupool SI-60+. TF-100

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    Re: SLAM help please!!

    If you have a separate valve for the main drain, you can open it just a little to get some flow, but not detract much from your skimmer suction. The only time my main drain valve is open all the way is when I'm blowing it out for the winter.
    20x40 in-ground Bella Blue Pebble Fina pool w/diving board, 1 HP Hayward Superpump, Raypak RP2100 335k BTU NG mV heater, Pentair Quad DE 60 filter, Pentair 261173 multi-port valve, Stenner 45MPHP10 pump w/15 gal tank, Intermatic ET1125CR dual electronic timer, 1.5" lines, two skimmers w/socks, Poolskim, vacuum line, ColorQ Pro 7 kit, TF-100 kit, speedstir, 2 froglogs, Dolphin Discovery Robot. Wine is the answer, what was the question?

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