Trying to lower TA

[crustfan]

Pool School says to add acid in front of a return. However I only have in floor popups. What's the best way? In the past I've just thrown in cups of acid in different places of the pool to spread out the acid. There's a guy on here who first dilutes a cup of acid in a bucket of water and then throws that in the pool which seems like the best technique. In the PS Lowering TA article, a point is made about adding "slugs" without really defining what they are or used for. It's an advanced point. After some research it seems that slugs are adding the acid all at once and that's bad because one can etch the pool, damage equipment,etc. And that people thought adding all the acid at once could make the process work better. It's a method that's shown to be ineffectual. For the newbie all we need to know is the correct method to add the acid and that's not stated very well anywhere either in the Lowering TA article or in the Recommended Pool Chemicals Article.

I don't think my SWG is providing enough aeration. I've been trying to lower my chlorine levels as well so I've got 5% SWG for 9 hours. I think I should also run my spa aeration. But for how long?

How does the SWG create aeration? Does the SWG need to be generating chlorine aeration to work? Probably so, and since I have a low percentage setting then there won't be much aeration.

 

[duraleigh]

Pop-ups in the pool floor are generally suction devices and do not return water to the pool but rather take it from the pool.

If you pool is configured with the pop-ups being returns, do they come up each time the pump is on? I can't imagine that but anything is possible.

In any event, the idea when adding acid is to place it where it is diluted the fastest so it will mix quickly into the pool.

As you have figured out, totally disregard the "slug" method.

Often on this forum, in our goal to cover every possibility, our responses to questions and our articles include things that are peripheral to the subject and end up confusing the beginner. It is a natural tendency to cover all the minutiae and we all need to work on being very concise.

The "Lowering TA" article starts the discussion about "slug" by saying "there is a common myth" but, I agree, it is information not pertinent to "How to" do it it but rather "How not to" do it.

 

[Bama Rambler]

Dave's thinking about floor drains and not something like the Caretaker system you have. Since you only have the pop-ups you should slowly pour the acid around the perimeter of the pool in a slow small stream. I'd also do it while the cleaner is running to help the mixing a bit too.

 

[crustfan]

My TA is 120 and I want to bring it down within range for a salt water pool. I read the article on lowering TA and it seems reason I'd want to do this is that a high TA in a salt pool causes the pH to rise too quickly.

I have some procedural questions.

How long after adding the acid do I need to wait to start aerating? I'm guessing it's important that you'd want the acid thoroughly mixed up in the pool. I read 30 minutes is ok.

How long and often should I run the spa aerator for before taking another set of readings? Probably up to me but it'd be convenient to run it while the dogs have their swim in the afternoon which takes about 30-45 min.

I'm thinking that if I add acid in the morning and run the aerator for 30 min while the dogs are having their 2:30 swim I could bring down the TA in the least troublesome way. Take a pH reading each day and a TA each week and it'll happen over time.

We've also been getting alot of rain here in Florida each day and I've been needing to drain the pool often. I don't think this changes TA but maybe the rain is adding some acid.

 

[chem geek]

As long as you aren't aerating right in the area where you've added acid, you can aerate at any time. You just don't want to splash low pH water out of the pool, but there's nothing wrong with aerating the water at one end of the pool while you are adding acid over a return flow at the other end.