First Test Results and Questions

[DDave]

Got my TF100 Test Kit today and here are the first results.

FC 4
CC 0
pH 7.3
TA 290 (seemed high so I tested again. Second result was 330)
CH 150
CYA <20 (filled entire tube and could still see dot)

So . . . from what I have gathered from Pool School, I'll throw out my interpretaton.

I'm thinking I need to get the TA lower. Get pH to 7.2 then aerate. What are the penalties for high TA besides more chemicals required for pH change? The trichlor pucks will add CYA so I am probably okay with that for now.

If I'm way off base, please let me know. Any other suggestions would be appreciated as well.

Also, is it okay to dunk the cylinders with the labels on them (chlorine cylinder and the CYA bottle) in the pool or should I use the graduated cylinder to get the water and then pour it into the containers with the labels?

Thanks.

Dave

 

[PaulR]

TA does seem high, but the bottles for that test often have a problem with static. Try the TA test again, but keep wiping the dropper with a damp cloth or tissue. Make sure the drops look normal size. If you're getting too-small drops then the test will be incorrectly high.

Trichlor will slowly add CYA over time; if you have a bucketfull that's one way to go. They are also somewhat acidic and will tend to keep the pH down.
--paulr

 

[JasonLion]

The TF100 uses waterproof labels, so dunk away.

 

[reebok]

I would comment that I use a bottle from pinch a penny to get my water, then test at a table outside. this makes it a lot easier so you're not tearing up your knees on the pool deck or getting baked in the sun. you probably already know this, but you need to get water from approx. elbow deep.

 

[Butterfly]

Hi DDave,

Sounds like you are doing your testing outside. I also collect my water sample in a bottle, but then I do my testing inside at the kitchen table.

It's much more comfortable for me and my test chems like staying inside where the air is comfy

 

[DDave]

TA does seem high, but the bottles for that test often have a problem with static. Try the TA test again, but keep wiping the dropper with a damp cloth or tissue. Make sure the drops look normal size. If you're getting too-small drops then the test will be incorrectly high.

Okay, I tested TA again making sure to wipe the dropper and making sure that the drops were normal sized. Got a TA of 230 this time.

So should I try to lower it or leave it alone?

Dave

 

[PaulR]

So should I try to lower it or leave it alone?

With your numbers I get a CSI of -.22 from the pool calc, assuming a temp of 65F. Even at 85F it's still just a bit negative. So.... there's a school of thought that says, if it isn't causing trouble, it's trouble free. That is, don't try to fix the number just because it's not in the "normal" range; you should have a real reason. If the high TA causes your pH to rise so fast you're constantly putting acid in, then yeah it's worth making a point of lowering it. But if the pH rise is tolerable, just tolerate it.
--paulr

 

[DDave]

So should I try to lower it or leave it alone?

With your numbers I get a CSI of -.22 from the pool calc, assuming a temp of 65F. Even at 85F it's still just a bit negative. So.... there's a school of thought that says, if it isn't causing trouble, it's trouble free. That is, don't try to fix the number just because it's not in the "normal" range; you should have a real reason. If the high TA causes your pH to rise so fast you're constantly putting acid in, then yeah it's worth making a point of lowering it. But if the pH rise is tolerable, just tolerate it.
--paulr

Actually the pH keeps going down . . . due to the trichlor I assume. So, I'll just leave it alone I guess. No need to fix it if it isn't broken.

Thanks.

Dave

 

[PaulR]

That is likely to change when you stop using trichlor. I know my pool has a pretty stable pH and FC when I have a few tabs in the floater, but I'm adding acid every week normally.
--paulr