Lowering Total Alkalinity with Homemade Aerator

[who4ever]

OK, I've read the articles about how to lower the TA of my inground. First add some acid to lower pH and TA, then aerate to raise pH, then acid, then aerate, and so on. Designing and building a simple PVC aerator that screws into the return doesn't seem so hard. My question is, though, I read the aerators lower the temperature. I don't want to lower the temperature. I don't have a heater and use a solar cover. I live on Long Island, it is August 21, and the temp is about 86. It almost reached 88 one day. I don't want it lower because at this point in the summer I doubt it will raise back up with just the solar cover.
Am I correct that the aerator will lower the temperature?
If so, is there an alternative way to lower the TA?
If I make a short aerator, just above the surface, and point it down, will that keep the temperature from lowering?
Thanks, Dave

 

[Divin Dave]

Dave,
anything that makes bubbles in the water will work. the thing about the spray is that the water splashing back down creates the bubbles and raises the pH.

A short aerator pointed back down will work fine.

 

[Donldson]

Firstly, welcome to TFP!

Yes, aerating will lower your water temperature. Before going in to options, I am wondering what your TA is and why do you need to lower it? Generally it isn't necessary to actively lower it as it will cause your pH to naturally rise and then you add acid to lower the pH and it drops the TA as well. With regular care your water will stabilize at the TA that works best for it.

 

[duraleigh]

Welcome to the forum.

If I make a short aerator, just above the surface, and point it down, will that keep the temperature from lowering?

Yes. Evaporation lowers the temp. Shooting the water sideways into the pool produces a lot of aeration but little evaporation.

 

[Agent99]

I'm going to assume your pool is well-established and that you haven't had the plaster refinished in a a while (like longer than a year or two) otherwise, fresh plaster will naturally raise your pH so that upon lowering the pH and the TA with acid, you'd be fine as the pH would rise on its own due to the fresh plaster. My pool has this issue right now so I'm going through lots of acid lately but I have no need to aerate as my pH creeps up in a couple of days easy.

I would do this:

Establish all your pool chemistry numbers first: pH, TA, CH, FC, CC, and CYA. If you don't have a test kit, I'd highly recommend TFTeskits (tfteskits.net).

Next, using Pool Math, figure out how much muriatic acid to add that will lower your pH by a certain amount. If your pH is 7.5, see how much acid you need to lower it to 7.2, for example.

Now lower the pH...measure and make sure of the new reading. Now measure once a day until your pH changes back to the first reading you made. Let's see how long it takes for your pH to bounce back to where it was. Lowering TA with this method will likely take you a long time but if you're patient and diligent and keep careful records, it can be done.

MOST pools' pH will usually RISE over time so I'm kind of assuming that will be the case with yours.