Become a TFP Supporter Pool Math Forum Rules Pool School
Results 1 to 14 of 14

Thread: SLAMing, CYA, prolonged green, and filter questions during SLAM

  1. Back To Top    #1

    Join Date
    May 2012
    Location
    Redding, CA
    Posts
    24

    SLAMing, CYA, prolonged green, and filter questions during SLAM

    Looking for help/advice.

    Heavy green algae burden, trying to reclaim the pool now. I did BBB last season, successfully, but lazily let it get out of hand this spring. It's swamp green.

    Starting:
    pH 7.2
    TA 110
    CH 220
    Borate 30
    CYA zero (!) - this surprised me as it was around 40 all last season

    I had 5 lbs of dichlor on hand, so added that (should bring CYA up to 12), and brought FC the rest of the way up to shock level with bleach, and have kept it up as per SLAM. I put another 2 lbs CYA in a sock in the skimmer. I put another 2 lbs CYA per the instructions on the bag (mix in bucket of warm water, pour slowly into skimmer). Not sure that was a good idea, but my thoughts were that it's how the manufacturer recommends adding it, and wanted to get the level up sooner than later. If and when all that CYA dissolves, it should bring it up to about 30.

    Here's my dilemma. The algae burden is so great that the filter grids (Pentair FNS Plus, 36, DE) clog incredibly fast. Backwash on my system has never worked well, I always remove and hose down the grids. It's impractical (though I may need to) wash them every few hours. So, I decided to just run the filter without the grids, figuring I'd just do the continuous chlorine shock to kill the algae, then deal with the grids and get rid of all the dead biomass after a few days. My other thought was that since I just added all the CYA, changing DE and washing grids every few hours would remove most or all of the not-yet-dissolved CYA. Does this make sense?

    After 36 hours of keeping the FC at or near shock level, the algae looks just as dark green as when I started. I would have expected it to lighten, to cloudy grey, or at least look like there's some progress. Shock level is 10 per poolcalculator, I've aimed for 12. Lowest it's been during SLAM (morning) was 6. Is there any benefit to shocking to a higher level? Even using the expected eventual CYA level of 30, shock level would be 12, which I've been doing. I did remeasure CYA, and it was up to about 15 (gross estimate, half-way between the 20 and the top of the cylinder in the TFT kit).

    Summary major questions:
    1) Leave filter grids out for now or run with them in and risk losing CYA?
    2) Any benefit to higher-than-calculated shocking?
    3) Should I have seen some progress in killing algae by now?

    Thanks!









    25,000 gal, plaster
    Pentair FNS Plus 36, DE filter
    3/4 HP Whisperflow pump
    BBB believer, trying to be disciplined enough to make it work!
    24000 Gal in ground plaster pool. Pentair FNS 35 DE grid filter. 3/4 HP single speed pump.

    400 Gal Hot Spring spa. Fiberglass.

  2. Back To Top    #2

    Join Date
    May 2012
    Location
    Redding, CA
    Posts
    24

    Re: SLAMing, CYA, prolonged green, and filter questions during SLAM

    FC 13 at 8 pm.
    FC 10 at 3:30 am, CC 0.5-1 (nearly clear with 1 drop, definitely clear with 2)
    Added 12.5% up to 14 ppm.

    CC has been about the same, 0.5, through the SLAM so far.

    Add'l info: first few cycles my FC dropped 3 ppm every 30 min. Busy life, I had a hard time keeping the FC truly at or above shock level, though last cycle it dropped 3 ppm over 7+ hours at night.

    Still trying to learn about ammonia. After some initial reading, I'm guessing it's a problem given my CYA went from 40 to 0 over winter. SLAMing should fix it, right?

    I see I'm one of dozens fighting the swamp this time of year.

  3. Back To Top    #3
    Mod Squad JohnT's Avatar
    Join Date
    Apr 2007
    Location
    SW Indiana
    Posts
    9,089

    Re: SLAMing, CYA, prolonged green, and filter questions during SLAM

    You'd probably see some CC if you had an ammonia issue. It's fairly normal to lose most or all of your CYA over the winter in a cold climate. Don't know about your more moderate winters and their effect on CYA.

    Running your pump without filtration, either by setting the multiport to recirculate or removing the grids is probably your best option until the algae is dead and you will be around to clean the filter as it clogs.

    Stay the course and keep the chlorine at shock level as best you can. You'll soon see the telltale shift to blue-grey from green telling you that you are winning.
    TFP Moderator
    20K Gallon 20X36 Vinyl Inground
    Hayward S244T Sand Filter with 1HP Whisperflo Pump. Liquidator C-201 and Solar Heat

  4. Back To Top    #4

    In the Industry

    duraleigh's Avatar
    Join Date
    Apr 2007
    Location
    Sebring, Florida
    Posts
    30,082

    Re: SLAMing, CYA, prolonged green, and filter questions during SLAM

    It is apparent from your post that you have a good grasp of the principles involved. As JohnT says, now you just have to stay the course and keep doing everything that you are doing.......it WILL start to clear...promise!

    1) Leave filter grids out for now or run with them in and risk losing CYA?
    2) Any benefit to higher-than-calculated shocking?
    3) Should I have seen some progress in killing algae by now?
    1. JohnT answered that....leave them out for now.
    2. Maybe, but we have to have a limit (much like a neccessary speed limit of 55, if we say 58 is OK, then how about 65? 80?) We provide guideleines and it's hard for us to say, "ignore the guidelines, put in what you want".
    3. Maybe, but your symptoms are all classic so it seems like you just really have a lot of algae growth to clear up.


    Yes, there are a lot of SLAMmers on the forum lately. Just wait 'til July - August when water temps get 85+
    Dave S.
    42k vinyl and concrete pool, 1.5hp pump, 140gpm filter
    TFTestkits , PoolMath , Pool School

  5. Back To Top    #5

    Join Date
    May 2012
    Location
    Redding, CA
    Posts
    24

    Re: SLAMing, CYA, prolonged green, and filter questions during SLAM

    Thanks guys!

    I'm happy to stay the course, just needed some reassurance especially that the no filtering (at first) wasn't detrimental to my SLAM. With further reading I've also figured out that keeping FC at or above shock is key... and when it drops even a few ppm below, the process just gets prolonged.

    FYI today I'm noticing just a little lightening of the green color. Hooray!




    25,000 gal, IG plaster
    Pentair FNS Plus 36, DE filter
    3/4 HP WhisperFlo pump
    BBB believer, trying to be disciplined enough to make it work!
    24000 Gal in ground plaster pool. Pentair FNS 35 DE grid filter. 3/4 HP single speed pump.

    400 Gal Hot Spring spa. Fiberglass.

  6. Back To Top    #6

    Join Date
    May 2012
    Location
    Redding, CA
    Posts
    24

    Re: SLAMing, CYA, prolonged green, and filter questions during SLAM

    Quote Originally Posted by duraleigh View Post
    2. Maybe, but we have to have a limit (much like a neccessary speed limit of 55, if we say 58 is OK, then how about 65? 80?) We provide guideleines and it's hard for us to say, "ignore the guidelines, put in what you want".
    There's a speed limit?


    25,000 gal, IG plaster
    Pentair FNS Plus 36, DE filter
    3/4 HP WhisperFlo pump
    BBB believer, trying to be disciplined enough to make it work!
    24000 Gal in ground plaster pool. Pentair FNS 35 DE grid filter. 3/4 HP single speed pump.

    400 Gal Hot Spring spa. Fiberglass.

  7. Back To Top    #7
    Richard320's Avatar
    Join Date
    Jan 2010
    Location
    San Dimas, CA (LA County)
    Posts
    18,768

    Re: SLAMing, CYA, prolonged green, and filter questions during SLAM

    If there's any debris in the bottom, it will slow the process down.

    Get the leaf rake and start dragging. Or vacuuming blind. Anything to get it out.
    16K freeform gunite with spa; Pentair 4000 DE filter; Century Whisperflow 1 HP; Pentair Minimax heater.
    Troublefree does not mean Maintenancefree. It's like brushing your teeth: You can spend a couple minutes a day and pennies a week or go to the dentist once a year and spend several thousand dollars.
    A pool is like a pet - you have to feed it every day, even the days you don't want to play with it!

  8. Back To Top    #8

    Join Date
    May 2012
    Location
    Redding, CA
    Posts
    24

    Re: SLAMing, CYA, prolonged green, and filter questions during SLAM

    Quote Originally Posted by Richard320 View Post
    If there's any debris in the bottom, it will slow the process down.

    Get the leaf rake and start dragging. Or vacuuming blind. Anything to get it out.
    Yes, I raked and raked blind, not pulling out any leaves any more. Also have the APS (pressure type) running, its bag is coming up empty at this point. Had to remove the screen from the APS hose, as it keeps clogging with algae and no pressure was getting to the sweeper.

    Unfortunately my brush fell off in the deep end, and I've tried and tried to find it with the leaf rake, no luck so far. I may have to swim in the swamp to find it (yuk).


    25,000 gal, IG plaster
    Pentair FNS Plus 36, DE filter
    3/4 HP WhisperFlo pump
    BBB believer, trying to be disciplined enough to make it work!
    24000 Gal in ground plaster pool. Pentair FNS 35 DE grid filter. 3/4 HP single speed pump.

    400 Gal Hot Spring spa. Fiberglass.

  9. Back To Top    #9
    Richard320's Avatar
    Join Date
    Jan 2010
    Location
    San Dimas, CA (LA County)
    Posts
    18,768

    Re: SLAMing, CYA, prolonged green, and filter questions during SLAM

    Quote Originally Posted by NocturnalDoc View Post
    Unfortunately my brush fell off in the deep end, and I've tried and tried to find it with the leaf rake, no luck so far. I may have to swim in the swamp to find it (yuk).
    I'd treat myself to a new brush head first. Maybe spring for a Wall Whale. It's unbelievable how well it works - you push down, it holds it against the wall. Much easier on the lower back.

    16K freeform gunite with spa; Pentair 4000 DE filter; Century Whisperflow 1 HP; Pentair Minimax heater.
    Troublefree does not mean Maintenancefree. It's like brushing your teeth: You can spend a couple minutes a day and pennies a week or go to the dentist once a year and spend several thousand dollars.
    A pool is like a pet - you have to feed it every day, even the days you don't want to play with it!

  10. Back To Top    #10

    Join Date
    May 2012
    Location
    Redding, CA
    Posts
    24

    Re: SLAMing, CYA, prolonged green, and filter questions during SLAM

    Quote Originally Posted by Richard320 View Post
    I'd treat myself to a new brush head first. Maybe spring for a Wall Whale. It's unbelievable how well it works - you push down, it holds it against the wall. Much easier on the lower back.

    Great minds think alike! That's the brush that's currently residing in my swamp.

    My problem is the holes in the pole are bent (actually ripped on one of my two poles) and the tabs don't hold tight. I got some "gorilla" heavy duty 4-pin V clips (made for the Gorilla line of pool telepoles), but it doesn't fit in the Whale, even if I cut off one pair of the pins. I think I'll have to drill new holes.


    25,000 gal, IG plaster
    Pentair FNS Plus 36, DE filter
    3/4 HP WhisperFlo pump
    BBB believer, trying to be disciplined enough to make it work!
    24000 Gal in ground plaster pool. Pentair FNS 35 DE grid filter. 3/4 HP single speed pump.

    400 Gal Hot Spring spa. Fiberglass.

  11. Back To Top    #11

    Join Date
    May 2012
    Location
    Redding, CA
    Posts
    24

    Re: SLAMing, CYA, prolonged green, and filter questions during SLAM

    Update:

    12 days after starting the SLAM, and losing a day and a half in the middle (broken part on filter housing, couldn't run filter), I could finally see and retrieve the wayward Wall Whale from the deep end, vacuum out the last bits of debris.

    Today:
    FC 9
    CC < .5
    CYA 30
    CH 260
    TA 130
    Borate 30
    ph ? (will check once the FC drops to maintenance level)

    Once again, TFP comes through for me, and I'm thrilled with this amazing resource. Thanks all!





    25,000 gal, IG plaster
    Pentair FNS Plus 36, DE filter
    3/4 HP WhisperFlo pump
    BBB believer, trying to be disciplined enough to make it work!
    24000 Gal in ground plaster pool. Pentair FNS 35 DE grid filter. 3/4 HP single speed pump.

    400 Gal Hot Spring spa. Fiberglass.

  12. Back To Top    #12

    Join Date
    May 2012
    Location
    Redding, CA
    Posts
    24

    Re: SLAMing, CYA, prolonged green, and filter questions during SLAM

    Also, for those in the midst of the process, don't give up! I think I had to clean the filters (either backwash or pull and hose down) about 15-20 times through the process. Up until the last 2-3 changes, the DE would clog with dead algae and the pump pressure would climb to 28 PSI (start at 8 PSI with fresh DE) in under 2 hours. Very frustrating, for sure, but I think it made it that much sweeter to see a clear blue pool and NOT have to change the DE again.


    25,000 gal, IG plaster
    Pentair FNS Plus 36, DE filter
    3/4 HP WhisperFlo pump
    BBB believer, trying to be disciplined enough to make it work!
    24000 Gal in ground plaster pool. Pentair FNS 35 DE grid filter. 3/4 HP single speed pump.

    400 Gal Hot Spring spa. Fiberglass.

  13. Back To Top    #13
    Mod Squad JVTrain's Avatar
    Join Date
    Feb 2014
    Location
    Central Minnesota
    Posts
    5,079

    Re: SLAMing, CYA, prolonged green, and filter questions during SLAM

    Quote Originally Posted by Richard320 View Post
    I'd treat myself to a new brush head first. Maybe spring for a Wall Whale. It's unbelievable how well it works - you push down, it holds it against the wall. Much easier on the lower back.

    Please talk me in to getting one of these!
    Joel - TFP Moderator - Minnesota - **Become a TFP Supporter!** Helpful Links: ABCs of Pool Water Chemistry - SLAM Procedure - Chlorine/CYA Chart
    40x20 Pool: 32K Gallons * Vinyl * Bleach Chlorination * Hayward S270T Sand Filter * Pentair SuperFlo 1 HP * Teledyne/Laars Heater * AquaVac Tigershark * TF-100 w/ SpeedStir
    Isolated Spa - 345 Gallons

  14. Back To Top    #14

    Join Date
    May 2012
    Location
    Redding, CA
    Posts
    24

    Re: SLAMing, CYA, prolonged green, and filter questions during SLAM

    Quote Originally Posted by JVTrain View Post
    Please talk me in to getting one of these!
    By all means, go ahead and splurge on one. It makes doing the walls a pleasure. The downside is it's clumsy on the steps and tight areas, and it does put more strain on the plastic V-clip and holes on the pole. I picked up a cotter-pin type thingy for about $2.50 at the hardware store to solve that problem.




    22,500 gal, IG plaster
    Pentair FNS Plus 36, DE filter
    3/4 HP WhisperFlo pump
    BBB believer, trying to be disciplined enough to make it work!
    24000 Gal in ground plaster pool. Pentair FNS 35 DE grid filter. 3/4 HP single speed pump.

    400 Gal Hot Spring spa. Fiberglass.

Posting Permissions

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