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

Thread: Possible Nitrate Troubles

  1. Back To Top    #1

    Possible Nitrate Troubles

    I have a 24,000g, vinyl, IG, sand filter, pool in Central NJ. I use just a floating puck for chlorine. I opened the pool in early April and have been struggling with the chlorine ever since. All other levels have remained at what you'll see below with no chemicals. In the beginning I was dumping 3-4 bags of shock, taking an instant strip reading and showing zero chlorine (pool store confirmed). I have used both the filter perfect and line cleaner perfect from Natural Chemistry (can't remember the name) products. I have also used PhosFree and Aqua Finesse. As of last week if I put 2 bags of shock in the pool I was able to get a dark purple reading on the sticks, however by the next morning the reading was back to either nothing or a very light shade of purple. I most recently shocked the pool on Wednesday night. Today I took a water sample to the pool store albite after it rained both Friday all day and today all day:

    Today's Readings:
    fc: .16
    tc: .35
    cc: .19
    pH: 7.3
    Hardness: 198
    Alk: 90
    Cyanuric: 79

    I also asked them to perform a Nitrate test which was only a stick test but came back in the 1-2 range (between the first and 2nd pink reading on the stick). Nitrites came back zero. I know if nitrates is the problem draining is my only solution, but I can't find what is an "acceptable" range for nitrates.

    Does this sound like a Nitrate problem or something else? Any help would be appreciated.

    Thanks,
    Mike

  2. Back To Top    #2
    Mod Squad jblizzle's Avatar
    Join Date
    May 2010
    Location
    Tucson, AZ
    Posts
    37,389

    Re: Possible Nitrate Troubles

    Well, now that you have tried all the "magic bullets" ... how about reading Pool School and learning to truly understand the chemistry in the pool?

    Phosphates = meaningless
    Nitrates = meaningless.

    You problem is the continues use of trichlor pucks which add chlorine and stabilizer. The chlorine is consumed, the stabilizer builds up. To keep a clear pool, the required FC is a function of the CYA level ... as the CYA goes up, you have to maintain higher FC ... puck will not be able to do this.

    Your CYA is too high, water replacement will lower it, then you need to switch to liquid chlorine so you stop adding any more stabilizer.

    Oh, and to follow the advice we provide (for free), you will really need to get yourself one of the recommended test kits and stop trusting the pool store ... who are in business to make money ... and by your post, they have gotten plenty of your money at this point.
    Jason, TFP Moderator
    18k IG pebblesheen pool, Hayward ProLogic P4 w/ T-15 SWG, Pentair 1HP 2-speed Superflo, Hayward 6020 DE filter
    500 sqft Heliocol solar panels, ThePoolCleaner, TF-100 test kit w/ SpeedStir
    Pool School + Test Kit + PoolMath = A TROUBLE FREE POOL
    If you found TFP helpful and we saved you money ... Become a TFP Supporter!

  3. Back To Top    #3

    Join Date
    Apr 2012
    Location
    SW Ohio
    Posts
    456

    Re: Possible Nitrate Troubles

    Excellent advice jblizzle...I would listen to him and save yourself a ton of money.....Mike
    18x52 intex ultra frame pool 6981 gallons, 1 HP LL pump with 19 in sand filter,BBB method,borax 50ppm
    leslies DPD test kit + fas-dpd chlorine test kit + borates test strips
    thru wall skimmer,hard plumbed with 2 returns 1 1/2 sch 40 pvc
    1 large fountain 1 inch sch 40 pvc,shut off ball valves on all

  4. Back To Top    #4

    Join Date
    Dec 2009
    Location
    Central Massachusetts
    Posts
    2,690

    Re: Possible Nitrate Troubles

    A couple of things.
    Your CYA is high, as mentioned above, but not terrible. But the test from the pool store may be inacurate. The phospates are meaningless, so yea, ignore that. The nitrates, or potential nitrates in the water are not necesserily meaningless. Their presence will increase the chlorine consumption until they are burned out in the form of combined chlorine. Hard to tell from your test results, but it apppears the CC may be high?

    At any rate, something is using chlorine in your pool. You need a proper test kit and keep you pool at shock level based on your CYA number until your chlorine is stable, and the CC numbers are <0.5 ppm or better yet, zero.
    Read pool school to learn how to shock your pool, and get a proper drops based test kit.

    Is your water clear otherwise?
    14,000 gallon IG, Vinyl. Hayward 3/4 hp superpump, Penatair IC40 SWCG, Pentair automation, Hayward sand filter, Aqua Comfort heat pump, Hayward 400k Lo-Nox LP heater.

  5. Back To Top    #5

    Re: Possible Nitrate Troubles

    The strangest part is that the pool is crystal clear; of course water temps in NJ have been extremely cold for April/May so Algea would have a tough time growing anyway.

    I appreciate everyone's feedback. It's probably not an exact science but to drain the pool to reduce the CYA levels how much do you think I need to remove? I guess in doing so I'd help both the CYA issue and potential Nitrate issue.

    Thanks again,

  6. Back To Top    #6
    JasonLion's Avatar
    Join Date
    May 2007
    Location
    Silver Spring, MD
    Posts
    37,879

    Re: Possible Nitrate Troubles

    Nitrates are not a problem. The nitrate level has no direct effect.

    This sounds a little bit like an ammonia issue, though if it was ammonia the CC level would be higher.

    Regardless the solution is to shock the pool as described in Pool School (not as described by the pool store).
    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

  7. Back To Top    #7

    Join Date
    Dec 2009
    Location
    Central Massachusetts
    Posts
    2,690

    Re: Possible Nitrate Troubles

    I wouldnt do any water drain at this point. Get a test kit, perform each test, and post up the numbers. In the mean time, you can add chlorine to your pool, just do it with bleach.
    For a CYA value of 80, your shock number is 31 ppm. To raise the FC to 31 from zero, you need to add 16 gallons of 6% bleach. And thats assuming your CYA is truely 80.
    14,000 gallon IG, Vinyl. Hayward 3/4 hp superpump, Penatair IC40 SWCG, Pentair automation, Hayward sand filter, Aqua Comfort heat pump, Hayward 400k Lo-Nox LP heater.

  8. Back To Top    #8
    Richard320's Avatar
    Join Date
    Jan 2010
    Location
    San Dimas, CA (LA County)
    Posts
    18,768

    Re: Possible Nitrate Troubles

    Quote Originally Posted by mminetti
    The strangest part is that the pool is crystal clear; of course water temps in NJ have been extremely cold for April/May so Algea would have a tough time growing anyway.

    I appreciate everyone's feedback. It's probably not an exact science but to drain the pool to reduce the CYA levels how much do you think I need to remove? I guess in doing so I'd help both the CYA issue and potential Nitrate issue.

    Thanks again,
    It is an exact science, actually.

    IF - and that's a big IF - CYA is 79 and you want it to, say, 50...(79-50)/79 = 37% replacement. Tap water has no CYA. Check the math. (.63 * 79) + (.37 *0) = 49.77. IF CYA is 79. It's a tough test to master and pool stores are notoriously bad about it.

    I have no idea what my nitrate level is. Nor my phosphate level. Nor my Total Dissolved Solids. Never been tested. They don't matter. But my water is so clear I can toss a coin into the deep end and call heads or tails from the deck.
    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!

Posting Permissions

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