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Thread: initial numbers, help please :)

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    initial numbers, help please :)

    Hi, so I went against the rules and before testing my water, I dumped enough bleach 12.5% to bring the FC to 20 because the water was so gross, that I didn't want to keep exposing myself to it until there was some FC in it..hopefully, that's OK.

    I tested the water this morning after leaving having poured enough bleach to bring it to 20 (assuming it was at 0, which i'm hoping was a safe assumption given the amount of algae in the water).. this morning, water certainly looks clearer...these are my results:
    pH 8.2+
    FC 8
    CC 0
    TA 120
    CH 130
    CYA less than 20

    so, I need to...
    pH: Lower my pH with acid
    FC: bring my FC back to 20 with bleach
    TA: add a little Baking Soda to increase TA (not critical, i think)
    CH: It's is super low.. and hovered around 240-260 last year. If I have copper in my water and didn't add those extra two drops of solution, would that skew my results this badly? how do I know if I have copper in my water? It's possible the pool closers added algaecide with Copper in it, right?
    CYA: This was low last summer and I bought stabilizer to bring it up, but that stuff is expensive.. I'm thinking of getting the pool to clear and sparkling and then using TriChlor tablets for the summer. Does that sound OK? If I do this, should I add some stabilizer now before I start using TriChlor? oh, and this week is overcast all week, so I'm thinking low CYA isn't that big a deal??

    Thanks so much for the help. I missed this place over the winter.. hehe
    25,000 gallon gunite pool with waterfall (built 2000 - owner as of 2009), Aerotemp / Aquacal heat pump AT12000-A, Hayward DE4800 Filter, AOS UST1202 Motor, Hydro-King T104P201 Timer, Meyco pool cover, Pentair Model 320 Auto Chlorine Feeder. Located in Massachusetts.

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    Mod Squad Bama Rambler's Avatar
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    Re: initial numbers, help please :)

    Your first plan of attacking the pH is good.
    With a CYA of 20 your shock level is only 10. I wouldn't bring it a lot higher than that.
    With a TA of 120 I wouldn't raise that at all. In fact I'd be trying to lower it.
    You should add some CH to the water but it's not a critical thing you can do it once you get everything balanced.
    Take a water sample to the Pool Store and have them test for metals.
    If you keep a check on your CYA fairly regularly then using tablets until it gets to 50 or 60 is acceptable then switch to bleach or liquid.
    Dave J. TFP Moderator
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    JasonLion's Avatar
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    Re: initial numbers, help please :)

    Just to emphasize something Bama Rambler already said: adjust your PH to around 7.4 - 7.6 before doing anything else.
    19K gal, vinyl, 1/2 HP WhisperFlo pump, 200 sqft cartridge filter, AutoPilot Digital SWG, Dolphin Dynamic cleaning robot
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    Re: initial numbers, help please :)

    oh crud, i got over anxious and dumped more bleach.. and forgot that CYA affected shock levels.. argh.. how much did i screw up?
    ok, going to run out and get some acid now.. hoping ace hardware sells something, since i'm limited on time right now.

    i wish i had some patience..
    25,000 gallon gunite pool with waterfall (built 2000 - owner as of 2009), Aerotemp / Aquacal heat pump AT12000-A, Hayward DE4800 Filter, AOS UST1202 Motor, Hydro-King T104P201 Timer, Meyco pool cover, Pentair Model 320 Auto Chlorine Feeder. Located in Massachusetts.

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    Re: initial numbers, help please :)

    It shouldn't be a big problem, assuming there is at least a little tiny bit of CYA in the water.

    Remember that you can't get reliable PH readings when FC is high. Your chlorine level will probably fall fairly quickly during the day. Wait till FC is again below 10 and then adjust the PH.
    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

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    Re: initial numbers, help please :)

    ok thanks.. a few other things..
    1) when I dumped the bleach, I also put 7 really old (like 2 yr old) tri-chlor pucks in the autochlorinator to start raising CYA. After 2 yrs, I assume there's little to no chlorine in them, is that right? Is that even useful to me or should I take them back out?
    2) I also found some old pH decreaser from prob 2 yrs ago (previous owner), but I should hold off on adding it to the pool until the FC is lower than 10? Is that right? Does this stuff lose it's strength over time? should I go out and get a fresh batch?
    3) What if my CYA Is actually zero.. it's possible that it is since i had a hard time raising it last summer.. what kind of problems might that cause?
    thanks again.. i will so NOTHING until i hear back

    Kicking myself for not having the patience to wait for responses ... i have to keep reminding myself that dealing with pool chemical levels requires patience.. which clearly, i lack
    25,000 gallon gunite pool with waterfall (built 2000 - owner as of 2009), Aerotemp / Aquacal heat pump AT12000-A, Hayward DE4800 Filter, AOS UST1202 Motor, Hydro-King T104P201 Timer, Meyco pool cover, Pentair Model 320 Auto Chlorine Feeder. Located in Massachusetts.

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    JasonLion's Avatar
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    Re: initial numbers, help please :)

    Using trichlor in the tablet feeder is fine right now. They dissolve very slowly so they won't make all that much difference, but they will help a little. After 7 years they will have broken down somewhat, but there is most likely some chlorine left in there.

    Both muriatic acid and dry acid have extremely long shelf lives, so they should be fine. You can go ahead and add about half as much as you think you need, but you will need to wait until the FC level comes down before following up to see how far PH actually came down and how much more you need to add to get to the PH level you actually want. Because your PH is out of range high, it is impossible to know exactly how much acid to add, so you will probably have to do a couple of cycles of adding acid, letting it mix in, testing the level again, and repeating until you reach your goal.

    If there has ever been CYA in the water the current level can't be zero. If it was literally zero the high FC levels would be likely to cause some limited damage, especially if your heat pump has a copper heat exchanger.
    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

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    Re: initial numbers, help please :)

    thanks again..
    just to clarify, the pucks are 2 years old and I put 7 of them into the chlorinator (b/c i thought the chloride was too little to effect the pool, but the stabilizer in them would be helpful)
    i just added some acid, how much time should i let pass before i check pH and FC again?
    thanks again!
    25,000 gallon gunite pool with waterfall (built 2000 - owner as of 2009), Aerotemp / Aquacal heat pump AT12000-A, Hayward DE4800 Filter, AOS UST1202 Motor, Hydro-King T104P201 Timer, Meyco pool cover, Pentair Model 320 Auto Chlorine Feeder. Located in Massachusetts.

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    JasonLion's Avatar
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    Re: initial numbers, help please :)

    If it was liquid acid, give it half an hour with the pump running before testing again. If powdered/granular give it an hour.
    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

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    Re: initial numbers, help please :)

    my latest test results are:
    pH between 7.2-7.5
    FC 8
    TA 120

    - should i be concerned that my pH dipped too low? at last check before this most recent test, it was still 8.2
    - should i address my low CH issues now? i checked pool calc and it says I need to ad 31 lbs of calcium chloride? is that stuff expensive? eeks! also, should i be concerned that it dropped so much since last summer? it was always in the normal range.. around 260, and now, it's half that.

    right now, i plan to vacuum out the dead algae and scrap the walls.. i'll wait until i hear back from folks before adding anything else into the pool.. after i finish scraping and vacuuming, i know i need to test FC again and then add more bleach to bring it to 10 again, but wasn't sure if I should tackle the CH before then.

    the water is looking much better, i can see clearly to the bottom of the shallow end and i can see the darkness of leaves and debris in the deep end..
    25,000 gallon gunite pool with waterfall (built 2000 - owner as of 2009), Aerotemp / Aquacal heat pump AT12000-A, Hayward DE4800 Filter, AOS UST1202 Motor, Hydro-King T104P201 Timer, Meyco pool cover, Pentair Model 320 Auto Chlorine Feeder. Located in Massachusetts.

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    JasonLion's Avatar
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    Re: initial numbers, help please :)

    Your PH is fine where it is. I don't see anything that indicates that it dipped too low. We do recommend PH be 7.5 to 7.8 normally, but anything down to 7.2 is fine in the short run.

    You can start raising CH, but take that slowly, in a couple of steps over a couple of days.

    Because CH dropped so much, there is some chance that you had some calcium scaling over the winter. If you don't see any scaling then don't worry about it.
    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

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