Low Borates, High CYA. What to do?

[thorin]

I am literally brand new at this so please bare with me.

Using the TFP calc, it states that for my 13K gallon pool, my borates are currently at 15 (desired = 50). My Ph is 7.3, CYA is right at 50, and Chlorine is at 1. I added Bleach per the recommended dose; however it also asks me to add a bunch of Borax to raise the borate level, while also asking me to add 255 oz of muriatic acid in order to compensate for the increase in Ph the increase in borates will cause.

Here is my concern: Won't muriatic acid ALSO raise the CYA?

Even more confusing to me, is that I thought that muriatic acid WAS CYA, or is CYA the compound produced from mixing muriatic acid and chlorine? So before I go and add more muriatic acid to my pool, can someone explain what that will do to my CYA?

Thanks!

 

[Mr Bruce]

Can you do this first, can you post a full test result like this:

FC:
CC:
pH:
TA:
CH:
CYA:

Borax raises pH, muriatic acid lowers it. CYA is stabilizer. Read this a few times: Pool School - Recommended Pool Chemicals

If the test results you posted are from a good test kit, the main thing for right now is to add a little chlorine, it is too low for a CYA of 50.

 

[Fingaling]

Muriatic acid is used to lower ph. It is not related to cyanuric acid (cya) which is used to protect chlorine from the sun.

Cya has to be added once and generally stays in the pool unless water leaves (backwashing, splashout, leak).

Adding the borax and muriatic acid will not affect your cya at all.

Just FYI: borates are an optional enhancement to your water quality. You may want to wait till you get a handle on everything else before deciding to add them, and since you live in the US, buying pure boric acid online(which adds borates without changing ph) may be an easier and cheaper route to do that.

 

[pinguy]

Hi Thorin.

Borates are completely optional. You don't need to worry about them right now.

Muriatic Acid is for lowering pH, it does not affect CYA. However 255oz is quite a bit, so I think we are still running in to some confusion from your pool math results. Check out the pool chemistry 101 and reccomended chemicals links below my post, that should clear up some confusion.

Do you have a reccomended test kit? We reccomend the k2006 or TF100, links are also below my post. If you have a kit, please post a full set of test results. If not, I'd order one ASAP. It would also help us out quite a bit if you put your pool's info in your signature.

Once we get the test results and pool info we can get you on the right track in no time.

 

[thorin]

Thank you everyone for such quick and comprehensive replies.

I have the TF100 kit.

Here are my test results as best as I could capture them:

G: 13,000
FC: 1 (Mine just said "Chlorine" . Is that the same as FC?)
CC: What is CC?
pH:7.3
TA: 100, best I could tell
CH: Not tested
CYA: 48
Borate: 15
Temp: 85 when tested
CSI: Not sure.


Picture of TFP Calc Results

 

[Mr Bruce]

CC = Combined Chlorine, testing directions here here: Pool School - FAS-DPD Chlorine Test

If the water level in the vial for the CYA test was between 40 and 50, you can round up to 50.

If the water is clear I wouldn't do anything other than get the chlorine up to the Target for a CYA of 50 (chart in sig). How's the water look?

 

[thorin]

Crystal. And I want to keep it that way

 

[pinguy]

Crystal. And I want to keep it that way

What type of pool surface do you have?

Numbers look good except for FC being low. How are you chlorinating your pool? For a CYA of 50, you want to keep your FC at 6-8 (see FC/CYA chart link below).

 

[thorin]

What type of pool surface do you have?

Numbers look good except for FC being low. How are you chlorinating your pool? For a CYA of 50, you want to keep your FC at 6-8 (see FC/CYA chart link below).

Plaster I think. Its a rough, coarse feeling stone like material

Bleach.

Not sure why CYA is high or how to lower. I don't have room for more water and no idea how to remove water just yet.

 

[pinguy]

Plaster I think. Its a rough, coarse feeling stone like material

Bleach.

Not sure why CYA is high or how to lower. I don't have room for more water and no idea how to remove water just yet.

50 CYA is fine

Do a CH test, that number is important for protecting your plaster.