Alk test won't work

May 25, 2007
766
PH in my dad's pool is very low, color is lighter than the 6.8 low end of the scale. I want to adjust it up tonight so tried to test alk so I could determine if I should use baking soda or borax and how much of which to get, but the HTH drop test won't work. The 5 drops I put in the 25ml sample are supposed to turn the water green, then you count drops of the titrant until it turns red. Problem is the 5 drops turn the water a dark pink. I tested it with tap water to make sure the indicator just hadn't gone bad, and it worked fine, also worked just fine in my pool a few weeks ago.

I seem to recall certain circumstances where the ALK test won't work, but can't find them now. His CYA is sky high, my guesstimate is 150ppm. Is it the high CYA or low PH that's preventing the test from working?
 
Sounds to me like your TA test is working fine but he has zero TA. If this is the case his pH is probably very low, like around 4 or so. Not a very good situation.

In situations like this I recommend adding enough baking soda to raise the TA to a reasonable level and then use washing soda or borax to get the pH back in check. This helps prevent overshooting the pH. Extremely low pH can damage metal parts like heaters so fixing this is a priority.

Does he use pucks? They are very acidic and probably caused the issue. If he is going to continue their use then maintaining a TA over 100 will help prevent this from happening again.

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Found this in the extended test instructions sticky-

Add 5 drops of R-0008 and swirl to mix. The solution should turn green or blue. If the sample turns red, pink, or yellow, you are done, your TA is zero, and your PH is very very low (4.5 or lower).

Sounds like exactly what is going on. I'll use baking soda. I assume the high CYA is the likely culprit?
 
Sounds to me like your TA test is working fine but he has zero TA. If this is the case his pH is probably very low, like around 4 or so. Not a very good situation.

In situations like this I recommend adding enough baking soda to raise the TA to a reasonable level and then use washing soda or borax to get the pH back in check. This helps prevent overshooting the pH. Extremely low pH can damage metal parts like heaters so fixing this is a priority.

Does he use pucks? They are very acidic and probably caused the issue. If he is going to continue their use then maintaining a TA over 100 will help prevent this from happening again.

From my HTC One via Tapatalk

Thanks. Yes on trichlor and dichlor use. He has a bad case of white mold going on, 2ppm FC with a CYA of 150ppm at least.

Trust me, I've lead him to the water but he just won't drink. When it all falls apart, I put it back together again, plead my case, and wait for the next time.

He needs to just go SWG and be done with it but he's stubborn.
 
I've never adjusted a pool this far out of whack. Pool math says if I add 282 oz (12k gal pool) of baking soda TA should go to 100, but PH should only bump .2. If I assume PH is 4.5 as stated above, PM says I need 35 boxes of mule team 20 to get PH back to 7.5.

Does that seem right?
 
Add the baking soda and wait until you can get an accurate reading on it. From there adjust your pH only enough to bring it from 6.8 to 7.5. You will have to do this a couple of times to see a result but will prevent overshooting.

From my HTC One via Tapatalk
 
My concern is the PH drop test reads lighter than 6.8 so all I know is that it is low. With the info that if the drop test shows ALK is 0 then PH is really low, like 4.5, it doesn't go up much with the baking soda, and if it doesn't it requires a BUNCH of borax to adjust it up according to pool math.

Or are you thinking if ALK is 0 and I get it up to 100 with the baking soda I'll see a much larger bump in PH from the soda alone?
 
At that low pH the baking soda can have a more significant reaction. You want to get your TA up. Then adjust your pH in several doses so you don't overshoot.

Don't add a bunch of anything based on guesstimates. Slow additions until you get in a readable range.

From my HTC One via Tapatalk
 

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He did for a while. His pool was perfect. He got tired of manually adding bleach at dusk. Tried to talk him into SWG, he also went for it but in the end reverted back to the pool store and has nothing but problems since.
 
one thing I might add, is to gradually raise the ph over a 2-3 week period.

I raised mine from 6.8 to 7.5 within one week and had cloudy water for two weeks
then metal staining afterward.

His could cloud too, staining depends on metals count in his water I suppose.
 
Added the pool math calculated amount to get the TA up to 100, but this morning it's only reading 50 ppm. Also added sodium carbonate (HTH ph+, no borax around here :( ) to get PH from 6.8 to 7.5, PH still not registering.

Plan to add more baking soda and PH+. Would love to see the PH take a big jump up. Figured out last night that they don't have a bypass on his heater, so the low PH water has been running through it the entire time.

If ALK indicator goes bad, does it not turn at all, or give you a less then or more than actual TA reading? Mine is a few years old, but seems to be working just fine, always stored in a dry cool place. Just curious.
 
No bypass on the heater is bad in this situation. It sounds like there may have been a negative TA situation, which I don't entirely understand but have read about a few times. It could also have been due to TA contributing to pH rise but since you can't measure that low I don't think you can tell which it may have been.

Definitely get the TA up quickly but be gentle working with the pH. If the copper in his heater was leaching in to the water then a sudden spike in pH could cause some unfortunate problems. Staining and green water being the most likely issues. I wish I could find the thread but someone posted pictures of a heater that was destroyed within months because of low pH. Your dad may have finally really gotten himself in to some trouble with his refusal to take care of his pool.

Or he may blame you. I know how fathers and pools can be ;)

EDIT: Here is what I was looking for: Maintain your chemicals correctly
 
...

If ALK indicator goes bad, does it not turn at all, or give you a less then or more than actual TA reading? Mine is a few years old, but seems to be working just fine, always stored in a dry cool place. Just curious.
Yesterday, out of curiosity, I tried the TA test in an old HTH 6-way drop kit, which has been stored (read, forgotten) at ambient temperatures on our screen porch since 2007 (ideal storage of test chemicals... NOT). K-2006 gave me TA of 80 ppm; the long-out-of-date HTH kit yielded TA of 70 ppm, and the color changes looked entirely normal. So, based on that limited experiment, I'm guessing that the TA test chemicals last a long time.
 
No bypass on the heater is bad in this situation. It sounds like there may have been a negative TA situation, which I don't entirely understand but have read about a few times. It could also have been due to TA contributing to pH rise but since you can't measure that low I don't think you can tell which it may have been.

Definitely get the TA up quickly but be gentle working with the pH. If the copper in his heater was leaching in to the water then a sudden spike in pH could cause some unfortunate problems. Staining and green water being the most likely issues. I wish I could find the thread but someone posted pictures of a heater that was destroyed within months because of low pH. Your dad may have finally really gotten himself in to some trouble with his refusal to take care of his pool.

Or he may blame you. I know how fathers and pools can be ;)

EDIT: Here is what I was looking for: Maintain your chemicals correctly

Thanks. Got the TA up to 150 (overshot on purpose given his sky high CYA and planned continued puck and dichlor use), PH is finally about 7.0. Found some borax so will get the PH to 7.5 and monitor for awhile, because I know he won't. We shocked the heck out of it a few days ago, no metal staining so far so hopefully I caught this before real damage was done. Time will tell.

- - - Updated - - -

Yesterday, out of curiosity, I tried the TA test in an old HTH 6-way drop kit, which has been stored (read, forgotten) at ambient temperatures on our screen porch since 2007 (ideal storage of test chemicals... NOT). K-2006 gave me TA of 80 ppm; the long-out-of-date HTH kit yielded TA of 70 ppm, and the color changes looked entirely normal. So, based on that limited experiment, I'm guessing that the TA test chemicals last a long time.

Thanks, very helpful and makes me feel better about the readings.
 
I guess without his cooperation, it would be very difficult to keep it up.... but given the white mold situation you really need to try to SLAM the h-e-double-you-know-what out of that pool. And the stuff loves to hide out behind the lights, in the ladders, any areas with less than stellar water movement, and anywhere else that is usually forgotten.

I *think* it's considered to be a biofilm, and if I'm correct, then it's gonna take a very high-FC SLAM, and need to be maintained at the high level longer than usual.

I would think that finding any way you can, to scoop as much of it as possible out of the pool... (Using buckets- you don't want to divide the "strands" of mold into smaller pieces using a net... Then it would just be harder to see & get out.) getting any of it out of the water would have to make it easier to fight in the long run.

Perhaps you can use some of what you fish out, and experiment, within a bucket environment, with what kinds of FC levels will be needed to eradicate the mold. And how long you'll need to SLAM. It's gonna be at least mustard levels, and probably higher than that!
I bet Chem Geek would know more. :geek:
 
White water mold is a fungus so is not a bacterial biofilm, but when it grows into tissue-paper like sheets it's thick enough that it takes more chlorine to penetrate deeply enough to kill it, hence high SLAM levels for an extended period of time to remove it (though physically removing as much as possible is always helpful). Whether this needs yellow/mustard algae SLAM levels or not is unclear. Normally we recommended an extended regular SLAM and that usually is enough.
 
Rangeball, just a quick question...do you suppose you dad abandoned TFP methods because of any physical limitation carrying the bleach? Is he elderly or in any way physically compromised, eg arthritis in hands, etc., and doesn't want to admit that's the issue?

If you have a hunch that's the case, you might want to see if he'd consider a swg. Just a thought.
 
Thanks all for the input. Pool is now in great shape, water looks like liquid glass, PH is perfect. I'll just keep an eye on it.

Swampwoman, that's it exactly. I thought I had him convinced to go SWG a few years back but at the last minute he backed out. It would really be ideal for him, he already has high CYA so we could replace water to get it where it needs to be, his plumbing is very accessible so installing the cell would be a 10-15 min job, and the cost of the unit since his is a smaller pool would be less than he spends per year on pool store chemicals.

Haven't figured out what's scaring him about SWG yet but I'm not giving up. I think it's because he buys his season worth of chemicals when they open his pool. I'll need to make a hard pitch again before next year's opening.
 

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