Why So Much Muriatic Acid

[HandsomeJack]

Hello,

I've been having some water quality issues lately (calcium hardness of 900!) and have a pool service so am taking more control myself. Been studying everything I can here and have the full TFT test kit and using it regularly. Because of the above-mentioned calcium issue I drained and re-filled this week. Just about done adding all the chemicals to get it well balanced for a fresh start and it looks great. So I reached out to my pool guy (this is a vacation home so we can't do it all ourselves as we can be gone for weeks at a time) to let him know what I did and to alert him to not add anything without testing or checking in with me. In the course of that discussion he was a bit evasive about how much they and how often they test but he did say that they add acid every week. Is there any valid reason to just toss acid in every single week? The numbers I found when starting to test on my own are below. I suspect that the super low alkalinity is the result of all that acid. From what I read, my water should be cloudy with all that calcium but it's actually been fine to look at (although flakes everywhere on the floor of the pool).


I'm hoping to be able to keep the pool service as I need regular visits and cleaning and inspection. Can I tell him to stop with all the acid now that we are almost ideally balanced? I've been adding it myself to get the TA down after the re-fill as it was 120 from the fill water. But it seems like that ought to be sort of stable once I get it right, yes?

Water Chem Before Re-fill:
FC - 2.35
TC - 2.99
pH - 6.7
TA - 40
CH - 900
CyA - 18
Salt - 4000

Thanks much,

 

[Bperry]

Hello,

I've been having some water quality issues lately (calcium hardness of 900!) and have a pool service so am taking more control myself. Been studying everything I can here and have the full TFT test kit and using it regularly. Because of the above-mentioned calcium issue I drained and re-filled this week. Just about done adding all the chemicals to get it well balanced for a fresh start and it looks great. So I reached out to my pool guy (this is a vacation home so we can't do it all ourselves as we can be gone for weeks at a time) to let him know what I did and to alert him to not add anything without testing or checking in with me. In the course of that discussion he was a bit evasive about how much they and how often they test but he did say that they add acid every week. Is there any valid reason to just toss acid in every single week? The numbers I found when starting to test on my own are below. I suspect that the super low alkalinity is the result of all that acid. From what I read, my water should be cloudy with all that calcium but it's actually been fine to look at (although flakes everywhere on the floor of the pool).


I'm hoping to be able to keep the pool service as I need regular visits and cleaning and inspection. Can I tell him to stop with all the acid now that we are almost ideally balanced? I've been adding it myself to get the TA down after the re-fill as it was 120 from the fill water. But it seems like that ought to be sort of stable once I get it right, yes?

Water Chem Before Re-fill:
FC - 2.35
TC - 2.99
pH - 6.7
TA - 40
CH - 900
CyA - 18
Salt - 4000

Thanks much,

Hey Welcome! Yes, tell him to stop. He’s going to wreck things with a pH of 6.7 and a TA below 50. It’s not very hard to test pH and add the appropriate amount of acid …if needed. Not doing that is just lazy and since it’s literally his job, very suspect.

Also, your chlorine and CYA are way too low. That’s asking for an algae outbreak. (That’s assuming we trust the test results, but we don’t because they didn’t come from one of the known reliable test kits). TFP has very specific recommendations and wisdom that’s developed over time and one learning I can to realize early on is the test kit deal). If you have to use a pool service, I’d make him use a better test kit and report back results and anything they did as a result.

 

[HandsomeJack]

Hey Welcome! Yes, tell him to stop. He’s going to wreck things with a pH of 6.7 and a TA below 50. It’s not very hard to test pH and add the appropriate amount of acid …if needed. Not doing that is just lazy and since it’s literally his job, very suspect.

Also, your chlorine and CYA are way too low. That’s asking for an algae outbreak. (That’s assuming we trust the test results, but we don’t because they didn’t come from one of the known reliable test kits). TFP has very specific recommendations and wisdom that’s developed over time and one learning I can to realize early on is the test kit deal). If you have to use a pool service, I’d make him use a better test kit and report back results and anything they did as a result.

Thanks so much. This was pretty much what I suspected but didn't know if there was maybe some possible (good) reason that he's doing this.

All of those values were before I drained and re-filled so they are way way better now. Just waiting for the new salt to fully dissolve now to do the final fine-tuning. When I spoke to pool tech yesterday I could see that he only had a few large individual bottles of Red/Yellow so I'm guessing that they are only checking chlorine and pH when they do bother to test.

Thanks again,

 

[BDY]

What test kit are you using? The recommended test kits don’t have decimals like that

Test Kits Compared

If you don’t have a smart stir the TF Pro is a really good deal - it’s worth the $$$

Re acid - it’s only needed to lower the pH as needed or if you want to do a specific technique to lower your TA.

 

[mknauss]

Your fill water TA is 130 ppm (Colorado River water). So as you add that water due to evaporation, the TA rises as does the pH. Sadly, weekly pool service cannot manage that very well as you likely need to add acid more often. Instead they add way too much at once, likely based on no test data. Without testing TA, they have no idea how much to add.

So, you either let them do what they do and try to recover when you are there, or move there and do it yourself.

 

[HandsomeJack]

What test kit are you using? The recommended test kits don’t have decimals like that

Test Kits Compared

If you don’t have a smart stir the TF Pro is a really good deal - it’s worth the $$$

Re acid - it’s only needed to lower the pH as needed or if you want to do a specific technique to lower your TA.

I do have the TF-100 kit plus the separate Taylor salt kit which I had purchased initially. The #'s above are from the pool store so I'd have a printout to photo/send pool guy. The #'s matched what I tested manually.

Thanks re: acid. I think that's maybe why they are doing it. Keeping pH too low because the calcium was so high. And now that it is under control it sounds like I can tell them to stop it. I did add myself yesterday for that reason. My fill water had alkalinity of 120-130. Down to 90 now but pH dropped too so I'm aerating and it seems to be working.

 

[HandsomeJack]

Your fill water TA is 130 ppm (Colorado River water). So as you add that water due to evaporation, the TA rises as does the pH. Sadly, weekly pool service cannot manage that very well as you likely need to add acid more often. Instead they add way too much at once, likely based on no test data. Without testing TA, they have no idea how much to add.

So, you either let them do what they do and try to recover when you are there, or move there and do it yourself.

I didn't realize that that is where my water came from but you are 100% right and that's exactly the # of my TA that I got on my first test before adding anything. And I have absolutely watched them open the jug and give it a long long pour as the last step during the maintenance visits. And no testing.

Your plan sounds like my future. Follow-up behind them every week or two and adjust. Which I suppose isn't terrible but I just want to be able to give them whatever little bit of instruction in hopes they might sort of agree.

 

[BDY]

Instead of following up along behind them, Why don’t you just jettison them and do it yourself? Use this forum, the pool school, and the test kits and save yourself a lot of $$$ and get your water TFP clear

How Clear is TFP Clear?

Not meaning to be critical - but you’ve come this far why not go all the way?

 

[mknauss]

Not meaning to be critical - but you’ve come this far why not go all the way?

The OP does not live at the home full time.

 

[BDY]

The OP does not live at the home full time.

Doh! I missed that point

Thanks