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Thread: This method just isn't working for me...what am I doing wrong?

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    This method just isn't working for me...what am I doing wrong?

    So, my CYA is 45 and I've been maintaining the pool above 5ppm. I had it at 10ppm when the CYA was 60 (the constant rain brought it down). Still, we're going through chlorine faster (for the third time since starting this method this season). I tested before adding chlorine and it was 3.5ppm, so for kicks, I added a gallon of 10% and 2 hours later, it's 7ppm. So, we're dealing with algae again (pool is still clear). No one has even went swimming for 2 weeks. All other tests are normal and no combined chlorine.

    I've been very careful with the CYA test. I study it in good lighting for like 15 mins until I'm sure I can no longer see the dot. So, what gives?
    AG pool is a 7,500, 200# sand filter, 2 speed pump and Taylor kit,

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    Re: This method just isn't working for me...what am I doing wrong?

    For one thing, you should probably be using a CYA value of 50 for your calculations. Halfway between 40 and 50 is way closer to 50 as the scale is logarithmic. You can tell that the gradations are not equally spaced on the vial.

    You need to slam if you have algae. Here are the directions: Pool School - SLAM - Shock Level And Maintain

    You can swim when the water is clear enough to see a swimmer in trouble in the deep end (check), your pH is between 7.2-7.8, and your FC is above your minimum, but below shock/slam level for your CYA as outlined here: Pool School - Chlorine / CYA Chart

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    Re: This method just isn't working for me...what am I doing wrong?

    I've noticed if we don't swim for long periods I have to brush more often, or I start getting signs of algae. It's an often overlooked part of the TFP method.

    It doesn't take long to pass the SLAM criteria if you caught it early. Then brusha, brusha, brusha, lol.
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    Re: This method just isn't working for me...what am I doing wrong?

    With the CYA test you should only GLANCE in the tube. If you see the dot with a GLANCE then go to the next line. Once you cannot see it at a GLANCE you can pour the water to halfway between the lines. If you still cannot see the dot at a GLANCE you call it at the higher number. No halfies like stated above.

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    Re: This method just isn't working for me...what am I doing wrong?

    If your CYA is 50 and you have algae, you need to SLAM by raising your FC above 20 and keep it there until the water is clear and you pass the OCLT.

    The bottom line is your FC is still too low and your algae is hanging on.
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    Re: This method just isn't working for me...what am I doing wrong?

    Welcome to the forum.
    This method just isn't working for me...what am I doing wrong?
    Well, we can make it work for you but you will have to do some careful testing and dosages of chlorine.

    Algae grows in your pool because you don't have enough chlorine.....it's that simple.

    Everybody ALWAYS says, "but wait, I know I put enough in because....." Nope, not enough chlorine. Whatever the reason may be and no matter what, algae will not grow in a pool that has adequate chlorine.

    So SLAM your pool. We'll help you all the way
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    Re: This method just isn't working for me...what am I doing wrong?

    I have two questions for you.
    1. Why do you believe you have algae?
    2.
    I study it in good lighting for like 15 mins until I'm sure I can no longer see the dot
    What do you mean by good light? You need to read cya in sunlight at waist height. Is that what you meant?
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    Re: This method just isn't working for me...what am I doing wrong?

    Thanks, everyone!

    Everybody ALWAYS says, "but wait, I know I put enough in because....." Nope, not enough chlorine. Whatever the reason may be and no matter what, algae will not grow in a pool that has adequate chlorine.
    This makes sense. I just don't understand it. I test once a day (twice if there's a reason) and make sure I'm adding the amount I get from pool math. I don't want to maintain levels that are too high, as I'm honestly not comfortable with the safety of chlorine. I was on Bacquacil for years until copper ended up in my tap water and kept eating the sanitizer for the entire season. I couldn't afford it anymore. Anyway, how do I maintain good levels? 5ppm should have been fine, but it apparently wasn't. At 7-9ppm, we did fine, but when I let it maintain at 5, we start blowing through chlorine again. I really don't want to keep the levels 7-9.

    From reading the replies, it seems that I'm viewing the CYA dot wrong. Maybe my method of doing the CYA test is wonky and that's the cause of the prob? I would view it in ANY way that I could possibly see the dot LOL. So, I'm supposed to view it at waist level with a quick glance? What type of lighting? Outdoor, inside, in sun, in shade? I watched a youtube video from Taylor and the dot was HUGE compared to my tiny one. When I try to see mine, the glare from any light pretty much hides it. It is TINY. The Taylor video was done in 2014, so I guess they changed the size or could I have a dud? I can take a pic tomorrow, if that helps?

    I appreciate all the help!
    AG pool is a 7,500, 200# sand filter, 2 speed pump and Taylor kit,

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    Re: This method just isn't working for me...what am I doing wrong?

    Quote Originally Posted by blessedmamato3 View Post
    So, my CYA is 45 and I've been maintaining the pool above 5ppm. I had it at 10ppm when the CYA was 60 (the constant rain brought it down).
    The rain shouldn't lower the CYA unless you are letting the rain overflow your pool or are draining before the rain.
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    Re: This method just isn't working for me...what am I doing wrong?

    I just wanted to give you some confidence in the levels we suggest here because you said
    I don't want to maintain levels that are too high, as I'm honestly not comfortable with the safety of chlorine
    I understand that our levels may seem high, especially considering the pools stores often say 1-3ppm max, but the effects are really moderated by the levels of CYA to ensure they are safe. This is based off of sound peer reviewed research from the '70's

    I thought these posts from jblizzle and joyfulnoise might help set your mind at ease. Note I have edited these for brevity


    We generally say it is safe to swim up to the shock FC level for your CYA level (see
    Chlorine CYA Chart). And this still corresponds to a lower "active" chlorine level than is typical of public / indoor pools that do not have any CYA in them. The "active" chlorine levels is less than 1ppm ... so it is less "harmful" to the skin/swimsuits/etc than a pool with 0ppm CYA and 1ppm FC.
    When CYA is present, roughly 95% of the FC you measure is chlorine that is chemically bound to the CYA molecule. The remaining 5% splits up into hypochlorous acid (the stuff that is good at killing algae and oxidizing bather waste) and hypochlorite ion (also a sanitizer and oxidizer, just less effective). The chlorine that is bound to the CYA gets released slowly as the HOCl/OCl- gets used up. When the chlorine is bound to the CYA molecule, it can be thought of as being "inert" or harmless. The FC you measure with your kit is the sum of all active chlorine species in the water - [HOCl] + [OCl-] + [HCy-Cl]. The actual concentrations of HOCl and OCl- in your pool water is at the parts-per-billion level.

    The reason why the chemical bottles are labeled that way is for EPA regulatory compliance. The EPA assumes chlorine is added to water with NO CYA present. So, if you extrapolated TFP FC levels to zero CYA, then you wouldn't have more than 1ppm FC in the water and even at that level the FC would feel harsh.
    I go by the thought the EPA drinking water limit for chlorine is 4 ppm and that is not moderated with CYA. If it is considered safe to drink at that level of active chlorine then our level which is much much lower and is only topically applied must be very safe.

    6 ppm FC with 50 ppm CYA has the same active chlorine level as only 0.1 ppm FC with no CYA. Most of the chlorine is bound to CYA and is effectively inactive, doesn't react significantly, doesn't outgas, has no skin absorption, etc.


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    Re: This method just isn't working for me...what am I doing wrong?

    Try watching this video Testing Cyanuric Acid with the TF-100 - YouTube the test should be done outdoors with full sun to your back
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    Re: This method just isn't working for me...what am I doing wrong?

    Perhaps I should have said, adequate effective chlorine. With a CYA of 50 ppm, FC of 3-4 ppm should be just fine for your pool.....assuming you don't let it go below that and are circulating and brushing properly.

    3-5 ppm works in thousands of pools so it will work for you, too, but there is something lacking in your maintenance procedures that is allowing algae to get a foot hold.
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    Re: This method just isn't working for me...what am I doing wrong?

    Quote Originally Posted by duraleigh View Post
    Algae grows in your pool because you don't have enough chlorine.....it's that simple.

    Everybody ALWAYS says, "but wait, I know I put enough in because....." Nope, not enough chlorine. Whatever the reason may be and no matter what, algae will not grow in a pool that has adequate chlorine.
    Heh. Passing the "do you have algae?" test means you have to throw out any other test result that doesn't predict algae.
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    Re: This method just isn't working for me...what am I doing wrong?

    Heh. Passing the "do you have algae?" test means you have to throw out any other test result that doesn't predict algae.
    ???? I do not understand.
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    Re: This method just isn't working for me...what am I doing wrong?

    "Official" results are great, but do you have algae? OP does and still has faith in the other tests that say there shouldn't be any.
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    Re: This method just isn't working for me...what am I doing wrong?

    Quote Originally Posted by RyanMcC View Post
    Heh. Passing the "do you have algae?" test means you have to throw out any other test result that doesn't predict algae.
    I'm not sure what you mean by that. Have you performed the OCLT to check your non-UV FC loss?
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    Re: This method just isn't working for me...what am I doing wrong?

    Ryan, its a valid question but doesn't negate tests because if one has visible algae then the required FC/CYA Chart ratio escalates accordingly.

    So for example,someone can report accurate, TFP-level results because they added FC that morning but can have visible algae because they dropped below the regular ratio prior. Once algae starts, regular FC values won't stop it...its gotten a start and can out-produce regular FC levels. SLAM levels are then required and maintained over time.

    So basically, nothing ironic to be found in the question. Its a required question to dx and assist

    So...Blessedmamma, do you have visible algae or not?
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    Re: This method just isn't working for me...what am I doing wrong?

    So...Blessedmamma, do you have visible algae or not?
    I do not. I just have FC levels that drop like a bad habit
    AG pool is a 7,500, 200# sand filter, 2 speed pump and Taylor kit,

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    Re: This method just isn't working for me...what am I doing wrong?

    Gotcha. So from one day to the next, what proportion of FC are you losing? Eg. If you dose in the morning to 6 or 7, what will your FC read the next morning, same time? Your min. at your cya would be 4 ppm (to not let it drop below.)

    But dosing too high actually wastes more chlorine.

    Nascent algae (not visible) can increase the FC demand. In an above ground pool, circulation can also be an issue. How many hours are you running your pump/filter?

    Here's a link to the test folks were asking you about earlier...its the best way to tell if you need to SLAM or not when you don't have visible algae:
    Overnight Chlorine Loss Test

    Lastly, other products, like stain remver (ascorbic acid) and even some types of algaecide can "fight" chlorine and use it up fast. Have you used any other products on your water other than bleach/chlorine and Muriatic acid or washing soda?
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    Re: This method just isn't working for me...what am I doing wrong?

    Well, that's what makes this so difficult to maintain: after a SLAM, I am maintaining perfect levels at about 1qt of chlorine a day consistently for a couple weeks. Then, one day, it starts using chlorine faster and then I can't keep up, as it's so erratic. That's when I start another SLAM. I have no idea what I'm doing wrong, but this is the pattern.

    When things are operating optimally, I will begin at say 8ppm in the morning and I'll test when the sun goes down and it's maybe 5ppm, so I'll add to bring back to 8ppm and repeat. I test twice a day. I add a quart a day consistently. Then that quart just stops working. To clarify, I dose based on test results, but I find that when things are working well, this is what I end up adding.

    I haven't done the OCLT yet, as I'm going through at least a gallon of chlorine a day to keep it at 16ppm, sometimes more. Isn't that a definite sign of algae? Doing an OCLT test isn't something I do unless it's at the end of a SLAM, as we aren't early risers around here lol. If I started one at like 7pm and checked it at 3am, would that count?
    AG pool is a 7,500, 200# sand filter, 2 speed pump and Taylor kit,

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