Become a TFP Supporter Pool Math Forum Rules Pool School
Results 1 to 5 of 5

Thread: Yellow walls are back with a vengeance!

  1. Back To Top    #1

    Join Date
    Jan 2014
    Location
    The Woodlands, TX
    Posts
    64

    Yellow walls are back with a vengeance!

    Apparently I was not successful with my first mustard algae SLAM last month.

    Quick question....

    Is there any reason I cannot go straight to M.A. SLAM level instead of doing a normal SLAM first?
    Brad

    15,000 gallon IG plaster with attached spa. Full Pentair EasyTouch system. IC40 SWG. TFT-100

  2. Back To Top    #2

    Join Date
    May 2014
    Location
    Current: Singapore Previous: Clayton, Victoria, Australia
    Posts
    584

    Re: Yellow walls are back with a vengeance!

    Normal SLAM instructions have been tweaked over the years to give the best algae-killing without bleaching the pool.
    Chlorine loss is a percentage of starting chlorine levels, you lose more chlorine going straight to M.A. SLAM levels.
    The recommendation is to do a normal SLAM until you pass all 3 criteria before taking the pool to M.A. levels for 24 hours.

  3. Back To Top    #3

    Join Date
    Jan 2014
    Location
    The Woodlands, TX
    Posts
    64

    Re: Yellow walls are back with a vengeance!

    Is it possible for me to be having just a .5 FC loss on the overnight chlorine loss test when I have what I believe to be mustard algae?

    I have yellow on my walls if I go a day without brushing them. My steps have significant yellow/brown clouds when I sweep them every day. It's got to be algae, right? If it were pollen, it wouldn't collect on the walls, correct? The pollen season is long over here in Houston.

    I went from 6.0 FC to 5.5 overnight. No CC.

    CYA - 45
    TA - 180
    Brad

    15,000 gallon IG plaster with attached spa. Full Pentair EasyTouch system. IC40 SWG. TFT-100

  4. Back To Top    #4
    Diver's Avatar
    Join Date
    May 2011
    Location
    South of Boston
    Posts
    450

    Re: Yellow walls are back with a vengeance!

    I've been having greenish-yellowish spots here and there for quite a while as well. I just finished doing MA SLAMing and the levels are still coming down and so far everything is clear.

    I also had a negligible FC loss during the spots appearance. With a solar cover on 80% of the pool, I would sometimes lose only 0.5ppm per 24 hours even though I had visual signs of algae. The spots might be attributed to poor circulation, but I would think it would still show up on the daily FF loss.

    The time line of shocking is also interesting:

    8:00 pm - starting shocking, initial FC 7.5, target FC (calculated) - 24.7
    9:30pm - FC: 23 (1.7 loss, some of it might still be due to UV, some to organics, the estimated 24.7 might be off a bit due to water level, etc)
    6:00am - FC: 22.5 (0.5 loss, sun was partially out already), CC:0

    So I basically passed the OCLT right away and started MA SLAMing the same morning.

    So I would have clear water, no CC, minimal FC loss and some visible green-yellow spots..
    26K In-ground Vinyl Pool | Hayward DE4820/SP0710XR50 filter | 1.125 HP Dual Speed Hayward Super Pump | Aquasol Solar

  5. Back To Top    #5
    JasonLion's Avatar
    Join Date
    May 2007
    Location
    Silver Spring, MD
    Posts
    37,879

    Re: Yellow walls are back with a vengeance!

    Low levels of mustard algae can sneak past the overnight FC loss test. Once it gets going the chlorine loss will be obvious.
    19K gal, vinyl, 1/2 HP WhisperFlo pump, 200 sqft cartridge filter, AutoPilot Digital SWG, Dolphin Dynamic cleaning robot
    Creator of PoolMath and Pool Calculator. Other handy links: Support this site, TF Test Kits, Pool School

Posting Permissions

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