Refill or treat?

[Jonathankpa]

Just purchased a home and inherited a spa/hot tub. Having issues even beginning to get the levels balanced. After adding baking soda several times, test strips are showing that the alkalinity has not risen at all.

Just had the water tested at my local spa dealer and here are the results, attached. Namely low ph, and high CYA and phosphates. Question: is this a situation to treat with phosphate remover and other chemicals? Or should I dump and refill the hot tub and start from scratch?

I don't see a major disadvantage to dump and refill, especially if it makes my job of balancing the chemicals easier in the long run. Again the history of this is unknown as we purchased a home with this hot tub, already full with water and unknown treatment history. So I wouldn't mind the baseline of knowing we have a fresh batch of water. But looking to anyone with more experience for recommendations. Thanks!

 

[ajw22]

Welcome to TFP.

Here is a recent thread with a similar problem. All the recommendations apply to you…

You need to start over, get a good test kit, purge the tub with Ahhsomme, and follow the TFP process. Phosphates are not your problem. Ignore them and ignore pool store testing and fixes.

Jacuzzi 280 - Green, cloudy, smelly

We’ve had the tub (Jacuzzi 280) for just about a month (we only wear certain bathing suits for the hot tub). I’ve followed all their steps in preparing the water and what it takes on a weekly basis. Opened it with Spa Boss spa shock, spa boss chlor aid, spa boss spa marvel and spa marvel alka...

www.troublefreepool.com

 

[Mdragger88]

Here’s the guide

How do I use Chlorine in my Spa (or pool)?

If you have a question about any information within this Sticky, please start a new thread for yourself where you will receive very quick responses to your specific questions. Thank you! Introduction There are two main things to consider when maintaining your hot tub water, Water Balance and...

www.troublefreepool.com

 

[walkinpool]

You’ll have a much easier time learning water chemistry with a fresh fill. No brainer on a hot tub with a few hundred gallons of water.

 

[Jonathankpa]

Very useful info and glad I found this forum. Thank you guys for saving me the headache of the route I would have gone otherwise!

 

[Jonathankpa]

Update...

Here is the problem I've been having with my recently inherited hot tub. I drained and refilled it (well water -high in nitrates, hard, trace coliform - if pertinent). Achieved alkalinity of about 90 after it was initially high, then swung lower than expected based on what I added to lower it. Since then, the alkalinity has slid down over a few weeks to about 60. Instead of worrying about it, I've been focusing on trying to get pH balanced. I have been adding sodium bisulfate but it's not lowering the pH much at all. The hot tub is 400 gallons. I began by adding 1, then 2 and now 3 ounces of sodium bisulfate at a time (by weight, which my scale said was about a small medicine "cup"/"shot glass" about 3/4 full per ounce.) The pH stubbornly resists being lowered. From an initial reading of ?8.8 (if I'm remembering correctly), I've only been able to lower it to 8.2. I've probably added 10 ounces or so total of sodium bisulfate (I am keeping records; just writing this from memory). Lately, it doesn't seem to want to go below 8.2.

Most recently, today my pH test meter read 7.2 after leaving it in the water for a while, but I suspect that it's perhaps not properly working, or not temperature compensating. The pH meter takes a couple of minutes to stabilize the readout, and doesn't match the red drop test, which shows pH of the highest or second highest level. Test strips also confirmed that pH is still high.

I am hoping that this conundrum is familiar to someone. Thanks in advance.

 

[pjt]

How are you chlorinating?

Achieved alkalinity of about 90 after it was initially high, then swung lower than expected based on what I added to lower it. Since then, the alkalinity has slid down over a few weeks to about 60.

Don't chase TA. It's the least important parameter of water chemistry.

I have been adding sodium bisulfate

Use muriatic acid instead.

Most recently, today my pH test meter read 7.2

How are you testing? You need a proper test kit. TFTestkits.net

Test strips also confirmed that pH is still high.

Stop using test strips. Their inaccuracy causes problems.

 

[Jonathankpa]

How are you chlorinating?

Some kind of chlorine granules. I know my CYA is low/non-existent. Not sure what order to chase levels in, other than alkalinity, then pH, then chlorine.

Don't chase TA. It's the least important parameter of water chemistry.


Use muriatic acid instead.

Ok, I'll get some.

How are you testing? You need a proper test kit.

K-1000 "blue case" kit from Trouble Free Pools, with the see-through windows and red drops. Confirming via yellow pH test meter from same source, and test strips.

TFTestkits.net


Stop using test strips. Their inaccuracy causes problems.

Ok.

Other Ideas?

 

[Mdragger88]

Jonathan,
Fc is paramount & must be maintained above minimum for your cya level (you need to test your cya).
Follow the FC/CYA Levels & use the fas/dpd test to measure this not the yellow oto comparator block.
Each dose of dichlor (which I suspect is what your chlorine granuals are) raises cya by roughly the same amount as it raises fc - the fc gets consumed, the cya stays in the water
Dichlor is also acidic so it lowers ph, this must be taken into consideration.
Here’s the effects via PoolMath effects of adding

The guide I posted above instructs you to stop using dichlor when a cya of 30ppm is reached & then switch over to using liquid chlorine.
As mentioned above Don’t worry about ta until its 40ppm then use baking soda to bring it back up a little. Most hot tubs do best (have a more stable ph) with a ta of around 50.
Test your ph with the tub still (jets off). Dose with Muriatic acid with a target of no lower than 7.6, (if phenol red test indicates higher than 8.2 just use 8.2 as your current ph) Let that circulate about 15 minutes then test again.
If you are not below 8.0 add what poolmath indicates to reach 7.6 - continue this process until you get a reading in the 7’s. Many well balanced tubs rest at a ph of 7.8 so don’t sweat the final result so long as it’s in the 7’s.
The large ph drops/acid doses are what has lowered your ta. In a spa you will always be adjusting ph to keep it in range, it is the nature of the beast because of all the aeration. The goal is not to find the “perfect” ph & ta but to find the happy ph & ta for your spa which is the ph & ta at which you can make somewhat less frequent acid additions.
So in synopsis-
The order is ~>
fc (based on cya level) ALWAYS above minimum
ph in the 7’s
Any Ta above 40 is fine
Everything else

Hope this helps

 

[Jonathankpa]

Jonathan,
Fc is paramount & must be maintained above minimum for your cya level (you need to test your cya).
Follow the FC/CYA Levels & use the fas/dpd test to measure this not the yellow oto comparator block.
Each dose of dichlor (which I suspect is what your chlorine granuals are) raises cya by roughly the same amount as it raises fc - the fc gets consumed, the cya stays in the water
Dichlor is also acidic so it lowers ph, this must be taken into consideration.
Here’s the effects via PoolMath effects of adding
View attachment 392779
The guide I posted above instructs you to stop using dichlor when a cya of 30ppm is reached & then switch over to using liquid chlorine.
As mentioned above Don’t worry about ta until its 40ppm then use baking soda to bring it back up a little. Most hot tubs do best (have a more stable ph) with a ta of around 50.
Test your ph with the tub still (jets off). Dose with Muriatic acid with a target of no lower than 7.6, (if phenol red test indicates higher than 8.2 just use 8.2 as your current ph) Let that circulate about 15 minutes then test again.
If you are not below 8.0 add what poolmath indicates to reach 7.6 - continue this process until you get a reading in the 7’s. Many well balanced tubs rest at a ph of 7.8 so don’t sweat the final result so long as it’s in the 7’s.
The large ph drops/acid doses are what has lowered your ta. In a spa you will always be adjusting ph to keep it in range, it is the nature of the beast because of all the aeration. The goal is not to find the “perfect” ph & ta but to find the happy ph & ta for your spa which is the ph & ta at which you can make somewhat less frequent acid additions.
So in synopsis-
The order is ~>
fc (based on cya level) ALWAYS above minimum
ph in the 7’s
Any Ta above 40 is fine
Everything else

Hope this helps

That is a immeasurably helpful. I will attack this and see how it goes. Any tip on the best muriatic acid to get? I saw a "magic acid"on Amazon... Perhaps that?

 

[wireform]

Ma comes in two strengths a 14.something and a 34.5%. They both work just of the weaker one you will use twice as much. Make sure the app input has the correct % checked off otherwise you may overdue it by mistake.

 

[Mdragger88]

That is a immeasurably helpful. I will attack this and see how it goes. Any tip on the best muriatic acid to get? I saw a "magic acid"on Amazon... Perhaps that?

That is 1/2 strength for full strength $$
Try your local hardware/ big box stores as they are generally the best place to buy acid - it is available in different strengths - just be sure you input the strength u have in poolmath. A 2 gallon pack of full strength usually lasts me way more than a year & i also have a pool.

 

[Newdude]

It should be in the pool section of any store that has one. For HD/Lowes/Walmart that's usually in the outdoor garden area. But it's also available year round in any paint aisle / store.

If the strength isn't listed, look for any half-strength buzz words like ECO / GREEN / Low or No fumes. They'll be the weak ones.

 

[Jonathankpa]

While I'm working on balancing everything, I realized I don't have CYA (something I should buy, in order to add it? - vs. letting it simply build by use of my dichlor).

Looking into buying CYA, I ran across lots of these types of articles:

Sparkle Pool Service Elk River MN, Guaranteed Pool Service in MN | Sparkle Pool Service | Elk River, MN

bluefinpools.com

What do I do with this info?! CYA = bad? Or CYA in moderation = ok? Or ???

Still bewildered by what seems like the chemical jungle I must navigate before getting to use our hot tub!

 

[Jonathankpa]

FYI I ended up buying 20° Baume muriatic acid (spelling may be incorrect) 34.5% from Ace Hardware.

 

[ajw22]

While I'm working on balancing everything, I realized I don't have CYA (something I should buy, in order to add it? - vs. letting it simply build by use of my dichlor).

Looking into buying CYA, I ran across lots of these types of articles:

Sparkle Pool Service Elk River MN, Guaranteed Pool Service in MN | Sparkle Pool Service | Elk River, MN

bluefinpools.com

What do I do with this info?! CYA = bad? Or CYA in moderation = ok? Or ???

Still bewildered by what seems like the chemical jungle I must navigate before getting to use our hot tub!

That blog reaches a backwards conclusion to support what they want to sell you.

Yes, too much CYA with too little chlorine does not allow proper sanitizing.

Their solution is not to use any CYA which makes the chlorine very harsh.

The correct answer is to properly balance CYA with your FC level. Their examples talk about CYA levels of 50-150 PPM. We recommend a CYA level of 30.

That is why we have the FC/CYA Levels

The blog writer has an agenda of selling you the FROG mineral system. Stay away from Pool Store blogs. They all want to sell you something.

 

[Mdragger88]

While I'm working on balancing everything, I realized I don't have CYA (something I should buy, in order to add it? - vs. letting it simply build by use of my dichlor).

Looking into buying CYA, I ran across lots of these types of articles:

Sparkle Pool Service Elk River MN, Guaranteed Pool Service in MN | Sparkle Pool Service | Elk River, MN

bluefinpools.com

What do I do with this info?! CYA = bad? Or CYA in moderation = ok? Or ???

Still bewildered by what seems like the chemical jungle I must navigate before getting to use our hot tub!

This is because of the lack of understanding of the fc/cya relationship for most. Cya gets too high but people still maintaining fc @3 or less & boom under sanitized sess pool
If you follow the FC/CYA Levels
& the guide

How do I use Chlorine in my Spa (or pool)?

If you have a question about any information within this Sticky, please start a new thread for yourself where you will receive very quick responses to your specific questions. Thank you! Introduction There are two main things to consider when maintaining your hot tub water, Water Balance and...

www.troublefreepool.com

You won’t have to worry about that.
Fc above 2 or so without cya is quite harsh but jumping in @2ppm for any length of time will possibly allow fc to go to zero during your soak which is bad news bears & can allow for person to person transmission of pathogens so the recommendations here of 20-40 cya allow for a happy medium of comfort whilst allowing you not to drop fc below minimum for your soak.

 

[Jonathankpa]

That blog reaches a backwards conclusion to support what they want to sell you.

Yes, too much CYA with too little chlorine does not allow proper sanitizing.

Their solution is not to use any CYA which makes the chlorine very harsh.

The correct answer is to properly balance CYA with your FC level. Their examples talk about CYA levels of 50-150 PPM. We recommend a CYA level of 30.

That is why we have the FC/CYA Levels

The blog writer has an agenda of selling you the FROG mineral system. Stay away from Pool Store blogs. They all want to sell you something.

Thanks. Suspected that. Appreciate you confirming.

 

[Jonathankpa]

Still having trouble bringing pH down.

I'm now dosing with the muriatic acid 4 times what Pool Math recommends ( 4 tsp, instead of 1 tsp), trying to bring down pH. Meanwhile, pH seemingly increased from 8 to 8.2 over a few days.

I'm wondering how y'all are accurately measuring pH? I understand test strips are inaccurate. The blue kit using phenol red almost always shows a color indicating pH near 8, though was starting to tend towards 7.8 a few days ago.

And the pH test meter seems to read inconsistently, with the readout value swinging
and sometimes never settling on a believable value. Typically the meter starts reading high, and then drops in value. But it takes a long time to truly settle. I've checked it several times with the calibrating "7.2 pH solution" and it correctly reads 7.2.

I'm confused....my wife keeps saying we should hire someone to get the levels right, and I understand her frustration. But I feel I've paid too much $$ for chemicals and testing equipment to let a hot tub beat this electrical engineer. Aargh!

Ideas?

 

[Newdude]

Swap tips with another bottle and see if yours is off.

The PH is one the easiest tests is also the easiest to screw up. Being inattentive has gotten us all here because its too easy to be doing something else or having your mind somewhere else. 1.......2.......345. And 345 is more like 7 because it was a squirt and not nice perfect drops. So anytime a test doesn't make sense, slow it down.

If those don't work, while rare, some have found that 4 drops consistently puts them in range.