Become a TFP Supporter Pool Math Forum Rules Pool School
Results 1 to 10 of 10

Thread: Is this algae? UPDATED: SLAM Started

  1. Back To Top    #1

    Join Date
    Mar 2016
    Location
    James Island, SC
    Posts
    13

    Is this algae? UPDATED: SLAM Started

    We're in our first year of pool ownership. I'm guessing this is some sort of algae. What to do? Here's the background...

    Two weeks ago the water was crystal clear. We had a tropical storm come through and dump a lot of rain. Last weekend this yellowish pollen-colored stuff started showing up on the bottom and walls. And the water started getting cloudy. I brushed the pool and vacuumed last weekend.

    This Friday (6/10) I Tested the water and vacuumed.

    Test results 6/10:
    pH=7.8
    TA=80
    FC=2.5
    CC=0.5
    TC=3.0
    CH=100
    CYA=40-50
    Salinity=2840

    I added CYA, salt, and bumped up the % on the salt generator. I left the pump running and it has been running since Friday.

    I was out of town yesterday but just now tested the water again. The water has cleared up more since Friday but still not crystal clear. The yellowish is back on the bottom already.

    Test results 6/12:
    pH=7.5
    TA=80
    FC=5.5
    CC=0.5
    TC=6.0
    CH=100
    CYA=60
    Salinity=3500

    Here's the picture from just now. On my phone so give me a minute to get it up.


  2. Back To Top    #2

    Join Date
    Mar 2016
    Location
    James Island, SC
    Posts
    13

    Re: Is this algae?

    Overnight chlorine loss test should be the first step, correct?

  3. Back To Top    #3

    Join Date
    Mar 2016
    Location
    James Island, SC
    Posts
    13

    Re: Is this algae?

    Did an OCLT.

    9:00 last night:
    FC=6

    6:00 this morning:
    FC=5.5
    IG 16'x32' approx. 15,000 gal., vinyl liner last replaced in 2012, built in ???, Intellichlor SWG, Sand Dollar sand filter, old rusty looking GE pump, standard TF-100 test kit

  4. Back To Top    #4
    Texas Splash's Avatar
    Join Date
    Jun 2014
    Location
    South-Central Texas, Marion/San Antonio
    Posts
    12,981

    Re: Is this algae?

    Andy, you passed the OCLT which is good. That means there's not a tremendous amount of organic consumption. It doesn't mean however you are totally out of the woods. Because your FC and CYA were so low Friday for a SWG pool, I suspect your water was struggling. But before I go too much further, can you confirm which test kit was used to get those readings? I ask because your sig still shows "don't own a test kit". The validity of those test results is #1 right now. Thanks.
    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!

  5. Back To Top    #5

    Join Date
    Mar 2016
    Location
    James Island, SC
    Posts
    13

    Re: Is this algae?

    My bad. I need to update my signature. I now have a TF-100 kit. These results were with the FAS-DPD test, performed as written in the instructions with 10 mL.

    Also, assuming it was the right thing to do, I turned my SWG back up to 40% this morning to keep the FC from dropping again and still have the pump running 24/7 trying to either clear up cloudiness or at least keep it from getting worse.

    Plan to brush and vacuum tonight if I'm able to get home in time from work. Completely slammed this week.
    IG 16'x32' approx. 15,000 gal., vinyl liner last replaced in 2012, built in ???, Intellichlor SWG, Sand Dollar sand filter, old rusty looking GE pump, standard TF-100 test kit

  6. Back To Top    #6
    Texas Splash's Avatar
    Join Date
    Jun 2014
    Location
    South-Central Texas, Marion/San Antonio
    Posts
    12,981

    Re: Is this algae?

    Great! One quick verification ... your SWG was turned-off last night for the OCLT correct?

    So there's two schools of thought here ... ONE - Accept the passed OCLT, assume you are algae-free and pursue other options like poor circulation, pollen, or something else settling in the water. TWO - Upon looking/touching the stuff you determine it is algae but perhaps it didn't consume enough FC last night to impact the OCLT and SLAM. It looks like algae, brushes-up into a plume like algae, and feel a bit slimy. That is why we have 3 SLAM criteria after all. We can sometimes see algae (sometimes not at all) and know we need to SLAM.

    We do know that the water was a target for algae when levels got low, and it's warming-up fast. If it were me, I would SLAM. Simply take that FC level up to your SLAM level based on the current CYA you last test (60) which would make sure FC SLAM level a "24". Your water is clear and you've already passed an OCLT, so ideally you would hope any organic discoloration would be eliminated quickly. Then you could validate once again by making sure all 3 SLAM criteria were successful. After the SLAM, then increase your CYA you 70 as required fro a SWG pool. If your water clarity and readings are any indication, it wouldn't take very long at all. Hope this helps.
    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!

  7. Back To Top    #7

    Join Date
    Mar 2016
    Location
    James Island, SC
    Posts
    13

    Re: Is this algae?

    I turned my SWG to 0% output for last night, left the pump running.

    The water temp did rise quickly. We had the tropical storm roll through and the water was approx. 80 degrees. Had a hot week after that and the next weekend it was up the 86-87 degrees according to my cheap floating thermometer.

    Poor circulation could be a possibility. It's an old pool. Only have one skimmer, one "main" drain in a wall, and only 2 jets. I experimented with a vacuum for a couple days to shorten my manual vacuuming time, so I think that even lessened my circulation by taking up my skimmer for a bit.

    I does feel a little slimy. I do suspect it is algae. I'm thinking option 2 would be the best course of action to SLAM it anyways even though the OCLT was okay. The pool was very swamp like when we bought the house in March. It was shocked in early April by a local pool maintenance company and brought up to snuff. Possible that the original shock didn't quite kill everything and it took the recent FC drop into the 2's to allow it to grow again?

    Re: CYA level. I've been trying to raise it for over a month. I can barely get it to move. This last rise from Friday to yesterday is the most I've ever been able to get it moving.

    Better SLAM this thing ASAP. Fiance (and I guess me too), hosting a baby shower in 2 weeks. I know they're going to be wanting to use the pool. About how long, typically, does it take for the FC to drop back down to normal after SLAMming?
    IG 16'x32' approx. 15,000 gal., vinyl liner last replaced in 2012, built in ???, Intellichlor SWG, Sand Dollar sand filter, old rusty looking GE pump, standard TF-100 test kit

  8. Back To Top    #8

    Join Date
    Mar 2016
    Location
    James Island, SC
    Posts
    13

    Re: Is this algae?

    I started my SLAM yesterday afternoon. One question, does the algae and/or other organics in the water consume the chlorine at a quicker rate when the chlorine levels are high compared to when they're at normal levels?

    Reason I ask is because of my OCLT results. On my Sunday night OCLT prior to starting the SLAM, I lost 0.5 ppm (from FC of 6 down to 5.5). Started SLAMming around 4:30 yesterday afternoon. On my OCLT last night I lost 6 ppm (from FC of 28.5 at 10:30 PM to 22.5 at 6:30 AM.)
    IG 16'x32' approx. 15,000 gal., vinyl liner last replaced in 2012, built in ???, Intellichlor SWG, Sand Dollar sand filter, old rusty looking GE pump, standard TF-100 test kit

  9. Back To Top    #9

    Join Date
    Mar 2016
    Location
    James Island, SC
    Posts
    13

    Re: Is this algae? UPDATED: SLAM Started

    SLAM plus 24 hr mustard algae shock level is complete. Looking good now. It was nice weather all week but rained cats and dogs on Saturday evening in the middle of the mustard level shock.
    IG 16'x32' approx. 15,000 gal., vinyl liner last replaced in 2012, built in ???, Intellichlor SWG, Sand Dollar sand filter, old rusty looking GE pump, standard TF-100 test kit

  10. Back To Top    #10
    Texas Splash's Avatar
    Join Date
    Jun 2014
    Location
    South-Central Texas, Marion/San Antonio
    Posts
    12,981

    Re: Is this algae? UPDATED: SLAM Started



    Nice to hear you are all done. Have a great summer!
    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!

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •