More TA and Ph issues

[canman47]

I've read a bunch of posts about the TA/Ph relationship but I'm still not getting something right. TA is always going high and so is Ph. I know I need to get my TA down but can't seem to do it. It always seems to be 130. Several times I've used MA to bring Ph down to 7.0 but within a few days it's back up again. I have no way to aerate the pool unless someone has a suggestion for that so my Ph will be very low too when I dump all that acid in. The Taylor kit maxes out at 8.0 Ph so there's no way to know how much higher than that you are so it's a bit of a guessing game. Lately I've been adding a cup of MA every day but Ph still creeps up and TA stays at 130. Shouldn't it be coming down? Today I added 3 cups MA and got Ph to 7.6 but I'm sure tomorrow it will be up again. My well water is 7.6 last I checked. Do I just need to be patient and add daily doses of MA and wait for TA to slowly come down?

 

[mknauss]

Your fill water TA is likely 130 ppm or so. Test that.
Test pH every other day. Reduce to 7.2. Test TA at least once a week, preferably more, as you need the data for Poolmath to give you a proper amount of acid to add.

 

[pjt]

What's the TA of your fill water?

TA is the least important parameter. Focus on pH control, and your TA will lower over time with MA additions.

 

[canman47]

Well, that's the problem. TA of fill water is 450 so I guess I will be forever fighting Ph rise. I have to add about 2 inches a week due to evaporation. It's 100 degrees+ every day here.

 

[mknauss]

Whoa -- that seems a bit high. You show using well water. Is that true?

 

[red-beard]

Marty, my friend in in upstate NY has extreme carbonates in her well water, 350 TA when she tested.

 

[mknauss]

The OP is in Northern California

 

[canman47]

I'm in Chico ,CA. It's north Sacramento valley and we live in Ag land surrounded by Walnut orchards. Some Ag practices affect the water quality so may be the cause of high alkalinity in our well. We treat for several things for our drinking water but impractical to treat pool fill water. Sounds like I'll be buying a lot of Muriatic Acid.

 

[red-beard]

Some people put in a water softener and fill with that water. Not sure if it will also remove carbonates.

 

[canman47]

I've just done some reading on this. We have a water softener for drinking water . It reduces hardness but not alkalinity so that's no help. We have reverse osmosis for drinking water but it would take an industrial size unit for pool fill. What is strange to me is that alkalinity is very high but Ph is low. I just tested and well water has 7.2 Ph and 450 alkalinity. How does that work?

 

[Sunnydaze]

I've just done some reading on this. We have a water softener for drinking water . It reduces hardness but not alkalinity so that's no help. We have reverse osmosis for drinking water but it would take an industrial size unit for pool fill. What is strange to me is that alkalinity is very high but Ph is low. I just tested and well water has 7.2 Ph and 450 alkalinity. How does that work?

Are you by chance using a new bottle of r009 for the TA test?

 

[mknauss]

Once the water gets to atmospheric conditions and can outgas the CO2 the pH will attempt to rise to equilibrium for the TA.

 

[Toxophilite]

Once the water gets to atmospheric conditions and can outgas the CO2 the pH will attempt to rise to equilibrium for the TA.

That's a relationship of underground water's pH/TA I had not thought of or even known to consider. Though I have been able to keep a fairly constant TA of 80 with 260 fill water, how does that play to aeration if one day I do decide not to run the spillover all day? Would I then be right back to my original 120 or so TA like the OP?

 

[mknauss]

Aeration increases the release of CO2 from the water. That is what pushes the pH higher.

 

[mknauss]

 

[Toxophilite]

Thanks! I actually had just found out TFP had that tv section from another thread and watched that vid earlier!! Great resource! I guess I'm thinking the order of water coming out of ground to fill. pH of water seeks equilibrium to TA as it enters environment and then able to outgas CO2. pH increase, TA decrease, by measure. My fill water sees environment when it leaves the tap to my pool. If I remove some of the aeration at pool, will then my acid demand decrease and my TA increase based on new water added? If I'm off chasing a rabbit, whistle me home!

 

[mknauss]

To a point. Once TA gets high enough, pH rises pretty quickly.

 

[canman47]

I watched the video and it was really informative but sounds like I'm kinda screwed with my high alkalinity fill water. The conclusion was with that kind of water to fill as little as possible. The pool does have a cover but it's a real pain to get off and on and we go in almost every day. I add water once a week and wonder if I should just do a heavy acid application on that day or should I add acid every day?

 

[canman47]

That's a relationship of underground water's pH/TA I had not thought of or even known to consider. Though I have been able to keep a fairly constant TA of 80 with 260 fill water, how does that play to aeration if one day I do decide not to run the spillover all day? Would I then be right back to my original 120 or so TA like the OP?

According to the video, aeration has minimal effect. The surface area of the water gives plenty of aeration.

 

[red-beard]

There are ways to treat TA from water. I know you can use lime as part of the process. You can look up water treatment possibilities on-line. I'm not saying a home version is cost effective, but there are ways to treat the water.