TA always high

[Jeffski]

If the TA in the tap water from my house is like 200, then I'm pretty much going to always battle TA and lowering it right?

When I fill my hot tub and test it's 200. Every time I refill my pool TA goes up. I have a vinyl pool, heater, rising PH, and am seeing some waterline scaling and would like to keep it lower.

It's a never ending battle. Not sure if there is a question here or if I'm just ranting.

[CarlD]

So read up on lowering T/A and keep it at the lowest end of scale: 80ppm.

Step one: add acid to get pH to 7.0-7.2
Step two: aerate water to raise pH back over 7.2.
Step three: test T/A level.

Repeat until T/A level is 80ppm.

[KurtV]

jeff,
You can probably also compensate for the high TA by keeping a lower pH (depending on your calcium level) in your pool. In the long run you'll end up using about the same amount of acid as you would following the TA lowering regimen that CarlD recommends, but in smaller, more frequent doses.

It basically comes down to whether you prefer to use a bunch of acid and effort over a few days or a week to get your TA down "permanently", or test and add small doses of acid daily to keep your pH at the low end of the acceptable range (I'd be guessing at the right number without knowing your calcium level). (I put permanently in quotes because you'll eventually have to repeat the TA lowering process as your high TA make-up water raises the TA in the pool.)

[Jeffski]

I know how to lower TA, I'm just frustrated that it will always be an issue. I drain and refill my hot tub 3-4 times per year.

[waterbear]

Lowering TA in a hot tub is an easy thing to do since the bubblers and jets with the air turned on full are an excellent source of aeration. The process goes very quickly in a hot tub. If you are using bromine and or MPS in the tub both of them are acidic so you want to run the TA on the higher side anyway. When you fill just lower the TA to the lower side (maybe about 80-90 ppm) and then when you add fill water you won't be raising it that much. If it gets too high then you might have to lower it again.

[Jeffski]

Yeah I'm sure your right but I'm still using the cheapo test kit and it won't test PH in the tub... just looks blue. I'll get the FAS-DPD test kit and then maybe it will be easier. Thanks.

[waterbear]

If you are using bromine in the tub then you need a special FAS-DPD test that is calibrated for bromine (taylor K-2106 is the complete kit. I forget the number of the stand alone bromine FAS-DPD test for bromine). You can alwasy use an OTO test since you are only interested in total bromine. Many of the cheapie test kits have a problem testing pH in a bromine system because of insufficient halogen neutalizier in the reagent. The Taylor pH reagent does not have this problem.

[Jeffski]

I switched to chlorine last year when we put the pool in. I figured it made sense to use the same in both. Bromine always made the tub smell bad.

Any reason not to use chlorine for the tub? Seems like a lot of people prefer bromine but I'm not sure why.

[waterbear]

none at all! I actually prefer a chorine tub to a bromine tub. Clorine is a bit more work to maintain the levels but if you 'give it 5 minutes a day' like CarlD always says it's not a big deal! Bromine has a strong 'chemical' smell and many people are allergic to it.