Something isn't right, what am I missing

[Keaneswa]

My spa is about 2 years old. I was recently having trouble maintaining a chlorine level so I purchased Ahh-some and used it twice. Lots of foam but just a little biofilm. I drained and refilled it. Added calcium chloride to get CH to 140. Added baking soda to get TA to 70 which increased Ph to 8.2+ (max of the scale). Using the app I calc how much muriatic acid to add which I put in. Ph was still 8.2+ so added muriatic acid twice more. Ph still read 8.2+. I tested TA again and it was down to 30 with Ph 8.2+, so I thought I should test borates. All I have are the Taylor test strips (if there is something better pls let me know), I use DPD for everything else. I did the test 4 times and it looks like borates are above 100 but this is hard to read. I have not added any borates and on my last fill I believe I had to. My last borate reading 4 months ago was ~50. I am also getting a lot of clean white foam when the spa is running which I didn't have before. I have added a couple of pics of the borate test results and the foam. Image 489 is the borate test strip prior to dipping it in the water, 490 is post-dip.

Any thoughts on what I may be doing wrong would be appreciated. Thanks for the help!

 

[Methuselah]

I would start by giving the sticky a read. It's pinned to the top of this forum.

It's never a good idea to work two chemicals against each other to adjust the TA, what was TA reading before you added baking soda? Also, adding two much too fast or close together can precipitate and make the water cloudy. Whatever you add give it some time between.

I see in the pic with the foam you have a water feature going and wonder if you also have aeration turned on. Both will drive up PH. First order of business should be turn off features and aeration and slowly add some MA calculated on this site's calculator using 8.2 PH starting point and wait a bit for it to settle before dosing again.

I'm no expert by any stretch, but hopefully someone else will chime in --- I can tell you that having borites in there before you get the water balanced will make the readings a bit harder to influence because it buffers PH change. Did you do a partial water change (?), it is strange that you have a borite reading unless you added it on purpose... .

What kind of kit are you using to test FC, CYA, ALK, CH, and PH with?

Your biggest concern should be to try and get ALK in the 40-60 range, then work on your PH. If PH is too low, use aeration to coax it up.

There's a link on bottom, old poolmath webpage that will give you the calculator

 

[Rocket J Squirrel]

All I have are the Taylor test strips (if there is something better pls let me know)

Why, yes, there is something better. We don't trust test strips around here, we prefer one of two test kits which use Taylor liquid reagents.

Pool Test Kits - Further Reading

www.troublefreepool.com

 

[Keaneswa]

Thanks for the reply. I'm using the Taylor K-1005 for testing everything but borates, also using the TFP Pool Math app to determine how much to add. I did a complete water change. After adjusting CH I first adjusted TA before trying to adjust Ph. Initially it was 30, then after adding baking soda I waited an hour and had a TA of 70. Then tested Ph at 8.2. I then added muriatic acid 1-2 oz at a time (waiting an hour or two between doses) to try to get the Ph down but all it has done is drop the TA down to 30 with Ph staying at 8.2+. The water is very clear. That is when I started to look at Borates. Not sure if test strips can go bad, but I am assuming there shouldn't be any borates in my public tap water, so it should be 0.

Good call on the aerators/waterfall. I usually never have them on but turned them on when adding the Ahh-some. One other random question, if I never have the aerators on and a couple of jets closed would stagnate water build-up behind them? I was wondering if this was causing the issue I had before doing the water change trying to maintain a good chlorine level.

 

[mknauss]

No real need to test for borates. When you do a drain and refill, add enough boric acid to get to 50 ppm. Then just leave it until the next drain and refill.

 

[bradgray]

Did you rinse your filter during the refill?
Had anyone been in the spa since refill?
You mention borates; what brand did you use in your last fill?

In my experience, clean compounded (tall) bubbles like you have are telltale of sulfates from soap. And with low CH like you have, this can be easier to generate with less. Especially with your venturi jets opened.

But it could be any number of additives. Think about all the stuff (including people) that has been in the water; anything stand out?

 

[Keaneswa]

No one has been in the tub since I filled it. I have not added any borate just tested it as the Ph readings were so off. The filters were in the tub (not filter well) when I used the Ahh-some, but I just realized I didn't rinse them afterward. Maybe that is what is causing all the problems.

 

[Methuselah]

Could be (filters need rinsing)

You said trying to keep chlorine in it. If it's too high it can read zero. Not only that, but high chlorine level will make PH read wrong. I think falsely high?

Do an OTO test on chlorine. If dark you'll have to wait for it to come down or neutralize some of it. In the meantime, it may be possible to dilute your sample to get a proper PH reading.

Lots of if. We have some experts here ... I hope one or two will chime in, but the pool school feature likely has the specifics I left out.

 

[Mdragger88]

Definitely need to rinse the filters or the residual ahhsome in them will be foaming.

If fc is above 10ppm ph will read incorrectly (often falsely high) as @Methuselah mentioned so don’t adjust ph until it comes down below 10ppm.

In a small spa it is easy to over do baking soda so be sparing & aim for ta of 50/60 before adjusting ph again. You can always add more if needed as you go along.

If ph wasn’t falsely reading high due to fc it was just higher than the readable value. In such cases you set “current” as 8.2 & target for 7.6 in
PoolMath
until you get a readable value. It may take several rounds.
As also mentioned, all the aeration shown in the pics will also increase ph without raising TA so just run the jets long enough to mix the chems well (5min or so) then check ph & ta to see where you stand.

If you haven’t added borates this fill there aren’t any. Ignore the strip.
The borate strips can/do go “off”.
There’s an expiration date on the bottle & as with all strips, once the bottle is opened moisture is introduced leading to their inevitable demise.
Like @mknauss said there’s really no need to test for borates in the tub since the water gets replaced fairly frequently (generally before the borate level gets depleted below useful levels).
Just Add the initial dose (50ppm) once you get a handle on the ph/ta & let it ride until the next refill.

 

[Keaneswa]

Thanks for the help everyone! It actually was the aerators throwing off the Ph readings so much. I always have them turned off and just turned them on for the Ahh-some treatment. Had no idea that they would have so large an impact.

 

[Mdragger88]

Thanks for the help everyone! It actually was the aerators throwing off the Ph readings so much. I always have them turned off and just turned them on for the Ahh-some treatment. Had no idea that they would have so large an impact.

It happens quick in a hot tub!
Good news though, if you ever need to lower your TA you will be able to do so quickly