Trying to balance... Need Help...

[Grove]

So I made another post previously trying to learn about what I will need to get this hot tub I recently acquired through a home purchase up and running and I have read and learned a lot through the responses I received.

Since acquiring the Hot Tub, as instructed, I purchased the ahhsome cleaner and gave it an excellent scrub down. It was not nearly as dirty as I expected after seeing some of the results other people get but there was some scum. I drained it completely and sucked the remaining water out of the pipes to ensure it was empty.

I have since refilled the hot tub and turned it back on and am now trying to balance. I presently am using the AquaChek test strips to test my levels as they were leftover and I'm trying to keep costs reasonable while I try to decide whether or not I will keep this tub or rip it out.

As instructed on the bromine forum post, I crushed up 6 bromine tabs and threw them into the tub to establish my "bromine reserve".

My test results are as follows:
Total Hardness: 250 - OK
Total Bromine: 20 - Very High - why so high? I only added the recommended 6 crushed tabs? I added some more fresh water last night and ran it for an hour with the top off hoping to burn some off.
Total Alkalinity: 240 - Very High - I need to get my PH down...
pH: 8.4 - Very High - I need to get this down...

Plugging this into the pool math, I was instructed to add 71 ml of muriatic acid to the tub. I did this and ran it for a bit to cycle through. I checked it again this morning. No change to my results. I added another 71 ml of muriatic acid this morning to try to lower the pH and will check again where I'm at when I get home. As I added it at 6AM prior to going to work I didn't have time to run it for long to cycle through, just a brief minute or two.

What am I doing wrong, why is my pH not lowering?

Did I add way too much bromine tabs?

Help!

** Edit **
I went out at lunch and picked up a Taylor K1004 test kit and will post results once done.

 

[dsmith99]

Your test strips are just not accurate at all. They either bleach out and bleed together plus they have such a wide range they can't even get you into the ballpark. I have never found them to offer good results at all.

Do yourself a favor and get a proper test kit, it is an absolute must have to properly care for a hot tub or pool. It may seem expensive but accurate testing to have safe and sanitary water is priceless.

How many gallon is your hot tub?

71 ml would be an enormous amount of muratic acid for an average hot tub, I dose mine with only about 5 ml to move it a couple tenths.

Can't offer much advice on bromine as I use chlorine in my tub.

 

[Grove]

Your test strips are just not accurate at all. They either bleach out and bleed together plus they have such a wide range they can't even get you into the ballpark. I have never found them to offer good results at all.

Do yourself a favor and get a proper test kit, it is an absolute must have to properly care for a hot tub or pool. It may seem expensive but accurate testing to have safe and sanitary water is priceless.

How many gallon is your hot tub?

71 ml would be an enormous amount of muratic acid for an average hot tub, I dose mine with only about 5 ml to move it a couple tenths.

Can't offer much advice on bromine as I use chlorine in my tub.

Thank you for your prompt reply.

My tub is 350 Gallons.

If I absolutely must get a proper test kit before deciding one way or the other if I actually want to keep this hot tub or not, which one should I get?

I see there is a Taylor Technologies K-1004 which is much more affordable on amazon when compared to the K-2006. Which one do I really need though?

Sorry for all the newb questions... appreciate the help.

 

[Grove]

I bought the Taylor K1004 test kit and have tested. My Bromine is still same as the test strip, very high at a very dark pink. My pH is also at 8.2 and it took me 19 drops to get the water to turn from green to "red" in the test tube. All of which according to the pool math is telling me to add more muriatic acid. I am concerned though as the above poster has indicated he's never had to add more than 5ml of muriatic acid...

 

[dsmith99]

That kit is better than strips but not quite enough. It does not use FAS-DPD for the chlorine/bromine test and it doesn't test hardness. FAS-DPD uses a color shift from pink to clear and doesn't leave you guessing at comparing color shades. FAS-DPD can also test much higher levels. You need to monitor hardness also to avoid scaling up your heater. My bromine experience is very limited so I can't really offer much advice on that. I know others use K-2006 or TF100 to test bromine and it has the other tests you need. I had a bromine tub years ago but use chlorine in my current hot tub and I drain and fill from my already balanced pool water and it works great.

What strength is the muratic acid are you using? If you are using weaker acid it will of course take more.

5ml of 31.45% muratic acid lowers my PH from 7.8 to 7.6, of course you are making a much larger change trying to lower from 8.2 so it will take more acid but 71ml should have given results.

TA is something you have to work down, you can't fix it all at once. You lower PH to 7-7.2 with acid, that will also lower the TA some. Then you need to raise PH back up without raising the TA. The way is to do that is aerate the water, that will bring PH back up then you repeat as needed until TA is where it needs to be, it's not a quick all at once process.

In 350 gallons 1.5oz (44ml) of 31.45% acid should lower PH by a full point from 8.2 to 7.2
The weaker percentages would take up to twice as much for the same change.

 

[Grove]

Thank you again for your response. I am indeed using 31.45% muriatic acid.

I think right now my issue is a lack of patience in that I need to bring it down slower than I'd like to see it happen in. When referring to the Taylor Dosage Charts, they don't seem to match what you're describing to me. These charts tell me to always bring my TA into recommended range before trying to adjust the pH. With that in mind, the chart says for a tub of 250 Gallons (they don't show 350 so I'm averaging between 250 and 400) it says to lower the TA by 10 ppm I need to add 25 ml of muriatic acid. I have read I should be lowering it slowly in increments so I guess to bring it down from where I'm at right now, 190 ppm, I need to bring it down 10 a day or so until I am within acceptable range then try to balance my pH.

 

[dsmith99]

TA acts as a buffer for PH so the higher your TA the more resistant PH is to change. PH should drop with acid additions but it will naturally want to come back up. As the TA comes down PH should become more stable. I've never really had to deal with a large TA adjustment as my water comes out of the tap at around 110.

You don't really want your PH below 7 as that's getting into the acidic range. I would add enough acid to drop down to about 7 and then see how fast the PH recovers then dose it with acid again and just work the TA down. Run the tub with the jets set to produce a lot of bubbles. That will aerate the water and cause the PH to rise. When you get your TA down into the 60-70 range the PH will be more stable and more resistant to PH rising by aeration.

My hot tub will almost stay between 7.6-7.8 and I rarely need to add acid, my TA sits at about 60 now. The ideal level for your water may be a little different. Finding a point where the PH is happy and in the correct range is the goal.