CH and TA relationship

[TomTinNC]

Greetings all,

Now that my swamp is cured, and is now lovely clearer than air, and going swimmingly......I have a question.

First off, today's numbers:

FC: 8
CC: <.5
TC: 8.3ish
TA: 80
CYA: 90
pH: 7.5
CH: 890* yep, I know its rediculous...but I have a vinyl lined pool.

Question: It was recommended by Duraleigh that I try and keep my pH a bit lower...like in the 7.4 range (I adjusted it after this test today...so it should be 7.4) in order to avoid the calcium from forming precipitant or scale. How about my TA? Does TA affect the high CH in any way? Is my TA ok at 80, or should I boost it with Baking Soda?

When I first tested the pool in February (when it was green as the Hulk) TA was 250. Acid/Aeration brought me down to a somewhat more reasonable level of 80. I'm not having any massive shifts in pH, and right now there is absolutely nothing wrong with the pool. Water is crystal. I think I grabbed some CC's because I'm due to vacuum and there are quite a few dead bugs on the bottom...skeeters and flies...gotta love the south. That's about it. I thank you in advance for any advice.

Tom

 

[jblizzle]

The TA is just a buffer for the pH. Having a lower TA will help prevent the pH from rising too fast. Since you MUST keep your pH down, you should definitely not raise it.

I can not remember your story (busy forum ) I assume you opted to keep your CYA up that high instead of changing water?

 

[TomTinNC]

Actually started out higher than that. I had pucked the pool for 3 years prior to finding this forum. I actually did replace about 40% of my water prior to de-swamping to get that CYA down. I'd like to get it down some more, but company is coming in a week, and I don't want to do anything to compromise the pool right now since it is doing fine. Once they go home at the end of June.....yikes for me there......I will do another water replace....probably around another 40%.

Tom

 

[jblizzle]

Sounds like a good plan to wait out the visitors.
Unfortunately, someone else is trying to clear a swamp in under a week before company ... it is a lot of work and stress.

 

[chem geek]

Scaling comes from any combination of high pH, CH and TA since all contribute to the saturation index. Because of your vinyl pool, there is no problem having the TA be even lower, but if your pH is stable where it's at then you can leave the TA where it is. If you find the pH rises too quickly, then you can lower the TA further.

 

[TomTinNC]

I gotchya. I'll keep my TA where its at, and keep the pH a bit lower to keep the calcium in solution. Pool is stable. Thank you again.