Become a TFP Supporter Pool Math Forum Rules Pool School
Results 1 to 8 of 8

Thread: Pre-opening algae treatment

  1. Back To Top    #1
    Water_man's Avatar
    Join Date
    Jun 2008
    Location
    Brookline, MA
    Posts
    390

    Pre-opening algae treatment

    One of my fellow snow-belt pool owners hasn't listened to my warning about the need to perform a spring pre-opening partial drain because snow and rain replenishment raises the water level above the cover, and the result is a mildly green pool. The issue was discussed here.
    I want to help the poor guy before the pool pro comes and opens the pool and starts the pump. Also, pool season here doesn't start until the end of May, so it may take some time before they actually open. Here's what I have in mind:
    First we're pumping water out so that the cover, which is infested with leaves and other organic products, is no longer touching the water. Then we are going to shock to 20 PPM (I have no idea what's his CYA level, so I'm assuming 50) and use two submerged pumps for circulation. Is anything wrong with this plan, until the pool is opened? What else can be done?
    This is my ticket for Heaven (when all's working..) :
    22k Gal gunite IGP, 38 SF Anthony DE filter, 1 HP Hayward Super Pump
    380k BTU Raypak Natural Gas Heater (Model RP405A) and solar cover
    8 gal Liquidator w/ 12% bleach, Dolphin Diagnostic Advantage robotic cleaner. 3800 ppm salt, 50 ppm borates.

  2. Back To Top    #2
    frustratedpoolmom's Avatar
    Join Date
    May 2007
    Location
    SWSuburban Chicago, IL
    Posts
    11,963

    Re: Pre-opening algae treatment

    I see nothing wrong with using pumps for circulation...however, I would put the pumps in first and let them circulate for several hours, then test the water. I wouldn't advise shocking without knowing what the CYA level is, or the PH level as well....I mean if his CYA is over 100, 20 FC won't do much...

    And if he has very low CYA, 20 could be too much....
    Helpful links: Pool School; CYA/Chlorine Chart
    24' round AG pool, 52" high, Raypak heater; Waterway 2 spd Pump;
    150 Sq ft. Clearwater Cartridge Filter; Former and DISSATISFIED "Pool Frog" owner
    http://www.PerfectlyClearPoolService.com

  3. Back To Top    #3
    Water_man's Avatar
    Join Date
    Jun 2008
    Location
    Brookline, MA
    Posts
    390

    Re: Pre-opening algae treatment

    Well, this was a classic case of improvisation under pressure. Thew weren't ideal conditions.
    A test kit wasn't available - the owner just ordered one, and CYA could be estimated at around 50 because of previous habitual use of trichlor. The cover not only had a "jungle" on it, but also a green paste of algae. Something had to be done quick before this pool becomes a swamp. A stitch in time saves nine, but you gotta do the single stitch.
    This is my ticket for Heaven (when all's working..) :
    22k Gal gunite IGP, 38 SF Anthony DE filter, 1 HP Hayward Super Pump
    380k BTU Raypak Natural Gas Heater (Model RP405A) and solar cover
    8 gal Liquidator w/ 12% bleach, Dolphin Diagnostic Advantage robotic cleaner. 3800 ppm salt, 50 ppm borates.

  4. Back To Top    #4
    frustratedpoolmom's Avatar
    Join Date
    May 2007
    Location
    SWSuburban Chicago, IL
    Posts
    11,963

    Re: Pre-opening algae treatment

    If he used trichlor it could easily be higher than 50.

    What? We get no pics?
    Helpful links: Pool School; CYA/Chlorine Chart
    24' round AG pool, 52" high, Raypak heater; Waterway 2 spd Pump;
    150 Sq ft. Clearwater Cartridge Filter; Former and DISSATISFIED "Pool Frog" owner
    http://www.PerfectlyClearPoolService.com

  5. Back To Top    #5
    Water_man's Avatar
    Join Date
    Jun 2008
    Location
    Brookline, MA
    Posts
    390

    Re: Pre-opening algae treatment

    Thank you, frustratedpoolmom, for following this thread.
    I didn’t think about pics when it happened, so I don’t have good “before.”
    After 18 hours of circulation, the water is clear and the bottom is visible. Water clarity isn’t bad, although not perfect. We stopped the “green devil” in time!
    Also, since the bleach was spread through the mesh cover, the algae gunk on top is gone!
    Test results: FC: 13.5 CC: 0.5 pH > 8.
    Plan of action until this pool is opened: Get muriatic acid and lower pH, keep FC above
    10 (test every 3 days) increase circulation by adding a third submersed pump. Can’t test for CYA yet because of shortage of reagent. Any comments?
    This is my ticket for Heaven (when all's working..) :
    22k Gal gunite IGP, 38 SF Anthony DE filter, 1 HP Hayward Super Pump
    380k BTU Raypak Natural Gas Heater (Model RP405A) and solar cover
    8 gal Liquidator w/ 12% bleach, Dolphin Diagnostic Advantage robotic cleaner. 3800 ppm salt, 50 ppm borates.

  6. Back To Top    #6
    frustratedpoolmom's Avatar
    Join Date
    May 2007
    Location
    SWSuburban Chicago, IL
    Posts
    11,963

    Re: Pre-opening algae treatment

    Yes. High FC makes the PH read a false-high. Don't adjust ph when FC is above 10, wait until the FC drops below 10 to retest the ph it may be at a normal level.
    Helpful links: Pool School; CYA/Chlorine Chart
    24' round AG pool, 52" high, Raypak heater; Waterway 2 spd Pump;
    150 Sq ft. Clearwater Cartridge Filter; Former and DISSATISFIED "Pool Frog" owner
    http://www.PerfectlyClearPoolService.com

  7. Back To Top    #7
    Water_man's Avatar
    Join Date
    Jun 2008
    Location
    Brookline, MA
    Posts
    390

    Re: Pre-opening algae treatment

    Quote Originally Posted by frustratedpoolmom
    Yes. High FC makes the PH read a false-high. Don't adjust ph when FC is above 10, wait until the FC drops below 10 to retest the ph it may be at a normal level.
    This is a good one, thank you for the reminder. How much does high FC affect pH? More than one pH unit?
    This is my ticket for Heaven (when all's working..) :
    22k Gal gunite IGP, 38 SF Anthony DE filter, 1 HP Hayward Super Pump
    380k BTU Raypak Natural Gas Heater (Model RP405A) and solar cover
    8 gal Liquidator w/ 12% bleach, Dolphin Diagnostic Advantage robotic cleaner. 3800 ppm salt, 50 ppm borates.

  8. Back To Top    #8
    frustratedpoolmom's Avatar
    Join Date
    May 2007
    Location
    SWSuburban Chicago, IL
    Posts
    11,963

    Re: Pre-opening algae treatment

    Quote Originally Posted by Water_man
    Quote Originally Posted by frustratedpoolmom
    Yes. High FC makes the PH read a false-high. Don't adjust ph when FC is above 10, wait until the FC drops below 10 to retest the ph it may be at a normal level.
    This is a good one, thank you for the reminder. How much does high FC affect pH? More than one pH unit?
    That I don't know...I just repeat what they tell me. Seriously, there is this explanation, but I'm on a need to know basis and all I need to know is don't test and/or adjust PH if FC is above 10.
    Helpful links: Pool School; CYA/Chlorine Chart
    24' round AG pool, 52" high, Raypak heater; Waterway 2 spd Pump;
    150 Sq ft. Clearwater Cartridge Filter; Former and DISSATISFIED "Pool Frog" owner
    http://www.PerfectlyClearPoolService.com

Posting Permissions

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