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Thread: Algae won't go away

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    Algae won't go away

    I have what I believe is mustard algae that has grown and continues to come back.

    I have been following the BBB method since I started my pool (12 x24 Intex vinyl) in 2013. With no issues till this year.

    We went on vacation for two weeks and lost power. When I got back the pool looked green. I turned the equipment back on and put bleach in the pool. I noticed the pool water was getting cloudy and my SWG was barely keeping up to FC 3-4. So I started running tests and I started shocking for algae. And that turned my pool very cloudly. So - I assumed I did have some kind of Algae at the bare minimum. I had some leaves and waste in my pool when I opened it this year.

    So, I pulled the SWG and kept bleaching.

    I kept the shock up until the OCLT test was good. But I got in a weird cycle. When I brushed it got cloudly and then when it settled it started to clear up again. It would start to clear up then I would backwash and waste from my filter (Pentair SD40) and when I went back to filtration, it put what I assumed was a stream of dirt back into the pool. Then it got cloudy again.

    SO - I figured out that even though I passed the OCLT test while running the filter 24/7 I had a bloom of what I assume is Mustard Algae somewhere in my filtration system. Now I started to notice that even with brushing the discoloration on the pool wasn't going away.

    I kept shocking with Bleach and the water started clearing up again. I passed the OCLT test this past Thursday night. Maintaining FC of 24. The walls still remained discolored. There water looked mostly clear but there was what looked like dirt in the seams on the bottom of the pool.

    Friday - Assuming I had a bloom in my filtration system that hopefully was gone, I vacuumed the dirt particles from the bottom of the pool into my filter and out the backwash. Then I took my filter apart, removed the media, checked the laterals for algae (none apparent) and bleached the inside of the filter, the laterals and put in fresh Zeoblast. At this time my water was clear and my test numbers were in line and my FC was holding at 24. I still had discoloration on the walls (but not all walls). I hooked everything back up and pushed dirt back into the pool again. UGH. The water got cloudy within 3 hours and I determined the bloom must have been in the hoses. So, I pulled the outer portion of the inlet and found the inner portion covered with a brown substance (algae of some variety).

    So I raised my FC back to shock level from 24 to 36 based on my CYA at the time.

    On Saturday morning I pulled a new set of numbers.
    FC 17
    CC 0
    PH 8
    TA 80
    CA 40
    CYA 25

    I had dropped from Shock over night. Probably due to all the brown particles that came from the inlet. So, I emptied water out of the pool till I was below the inlet and could remove it. I removed the inlet, valve and hose that had the algae at this time. I tossed the hose, I had another one on hand. And I soaked the inlet in 8.25% undiluted bleach. I added more bleach to the pool to get to shock of 36 and added MA because the PH was so high. Pool still running 24/7. I brushed the pool walls.

    Saturday afternoon - I took some water to a pool store to check to make sure my numbers were accurate. This is after draining water and adding more bleach & MA. About 3-4 hours after the addition of the bleach.
    Pool store told me my water was:
    FC 10 (but they only had the test that went to 10) 8(
    TAC 10
    Salt 4500
    Calcium 90
    CYA 50
    PH 7.6
    Copper 0
    Iron 0
    Phosphates 100

    I didn't buy anything. I came home and added more bleach to keep water at shock level.

    Sunday Morning
    FC 18
    CC 1
    PH 7.8
    TA 80
    CA 50
    CYA 35

    Added more bleach, brushed the pool walls.

    Sunday night
    Just checked FC it was at 24 so I added more bleach. Brushed the pool walls.

    Obviously I'm going through oodles of bleach. I've been going through 3-5 gallons a day.

    Monday morning
    Tried to pull FC, but ran out of drops at 20, so my FC is at least 10 and still very pink. I'm going to the store today and will get more drops.
    PH is back up to 8.0 or above
    TA is off the charts...can this be skewed if you have a high FC level? The TA turned light green, then blue, they yellow. And stayed yellow never turning red. I stopped at 50 drops. Assume something is wrong there.
    CYA - 20-25 had to get to the top before the black spot completely disappeared. Not sure if that is 20 or 25.


    So here are my questions / issues.

    1)The walls of the vinyl pool now have a discoloration that won't come off. I rub with undiluted bleach (8.25%) and it doesn't come off. I brush and it doesn't come off. I'm still at shock level for mustard algae and it's not coming off. Thoughts?

    2) I have been soaking the Intex Inlet in 8.25% undiluted bleach and rubbing off the substance (again I assume Mustard Algae) but there are spots that won't come clean. Ones I can't reach with the tooth brush to scrub that look just as dark after 48 hours in undiluted bleach as they do when I pulled the inlet from the pool. Is there a way to clean this? I assume this will come back if I can't clean it.

    3) When I started shocking my PH was 7.2 and slowly kept creeping up. After I emptied and replaced the filter media (this past Friday) I noticed my PH hit 8 or above (it stops at 8) so I added MA and dropped the PH to 7.6 it has started creeping back up and is back up at 8.0 (or above now).

    4) TA - This is a new problem today with my TA either stupid high or being skewed. Is that possible?

    Thanks in advance for any and all advice.
    Erica - NC
    12x24x4 Intex Pool
    Pentair SD40 - Zeoblast Media
    Intex SWG
    Aquabot

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    duraleigh's Avatar
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    Re: Algae won't go away

    1. What color is the discoloration?

    2. That's not mustard algae....Mustard algae is like a powder. Plastics "yelloe out" over time....you may need to replace it to get the color back.

    3. Virtually all pools rise in pH. Keep it below 8.0 with muriatic at all times.

    4. How much is "stupid" high?
    Dave S.
    42k vinyl and concrete pool, 1.5hp pump, 140gpm filter
    TFTestkits , PoolMath , Pool School

  3. Back To Top    #3

    Re: Algae won't go away

    1) see pic (dark brown)
    2) it comes off where I can scrub...just can't get anything in there.
    3) Okay will add more Muriatic Acid
    4) I stopped counting after 50 drops. I'll test again.

    IMG_2169.jpg

    - - - Updated - - -

    IMG_2159.jpg
    Erica - NC
    12x24x4 Intex Pool
    Pentair SD40 - Zeoblast Media
    Intex SWG
    Aquabot

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    domct203's Avatar
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    Re: Algae won't go away

    There are three (3) criteria to completing a slam:

    1) Water is clear (fail)
    2) CC's are 0.5ppm or lower (unknown)
    3) OCLT passes (pass)

    Let your FC drift down to your proper shock level. That does not look like mustard algae, and the extremely high levels of chlorine are going to ruin your liner & seals/gaskets/O-rings if you remain there for days at a time.

    Even if it were mustard algae, you only raise FC to mustard levels for 24 hours, and after fully passing a standard SLAM.

    http://www.troublefreepool.com/conte...tain-shockingl

    http://www.troublefreepool.com/conte...-mustard-algae

    Dom
    Dom - TFP Guide
    Intex 18' X 48" Ultra Frame AGP 6700 gallons | Two Intex CS8110 SWG's | Hayward Pro Series 21" Sandfilter | Hayward 1.5HP Power Flo Matrix pump | Hayward Thru-wall Skimmer | Wanda the Whale | 72 sq ft of Sungrabber Solar Panels with Hayward GLC-2P-A | Taylor K2006 Test Kit, Sample Sizer & Speed Stir | Click Here To Become a TFP Supporter!

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    Re: Algae won't go away

    This is what the inlet looks like now. Good accept for in the crevices, it keeps the brownish black color.
    IMG_2177.jpg

    This is a close picture of the substance IMG_2167.jpg
    Erica - NC
    12x24x4 Intex Pool
    Pentair SD40 - Zeoblast Media
    Intex SWG
    Aquabot

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    Re: Algae won't go away

    1) see pic (dark brown) - Wow! I have never seen anything like that....I believe something unusual has been added to your pool water but I don't know what

    2) it comes off where I can scrub...just can't get anything in there. - I have no clue

    3) Okay will add more Muriatic Acid - good deal pH is VERY important......keep it in the 7's

    4) I stopped counting after 50 drops. I'll test again. - Well, 50 drops is "stupid high"....double check your testing method. Using all the right reagents?
    Dave S.
    42k vinyl and concrete pool, 1.5hp pump, 140gpm filter
    TFTestkits , PoolMath , Pool School

  7. Back To Top    #7

    Re: Algae won't go away

    I had added more bleach and Muriatic Acid yesterday. Then was told to stop mustard algae shock b/c it didn't appear to be Mustard Algae. So I cleaned the inlet as best I could and reattached it to the pool. I added water back to normal level (approximately 10" of water) and ran filter 24/7 (accept for 10-20 minutes when I had to stop to reattach hoses to inlet).

    Water is still cloudly and brown particles are at the bottom of the pool. I have not brushed the pool walls yet today. If I do I imagine I'll disperse the particles into the water. Not knowing what it is, is that a good idea?

    Once my PH came down I was able to pull an accurate TA reading of 70. I imagine adding CYA is good at this point. But any suggestions on the brown particles?

    1pm Numbers
    FC 14
    CC 0
    PH 7.2
    TA 70
    CAH 60
    CYA 20
    Erica - NC
    12x24x4 Intex Pool
    Pentair SD40 - Zeoblast Media
    Intex SWG
    Aquabot

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