first reading w/ TF-Pro Salt....

[imrj99]

the pool was resurfaced just a bit over a year ago, surface and water look great, am just worried about these readings and the main thing right now is that its taking a lot to keep pH levels from going high....am using maybe about 4lbs of dry acid a week....salt level was 3500ppm (its a salt chlorine generator). My pool is in Miami, FL area.
Do i really need to dump half the pool water with replacement?

 

[Texas Splash]

Right now, yes. You need to exchange some water to lower the CYA. If you don't have algae, then you don't have to exchange half. Perhaps about 30-40% will be enough. As a salt pool, getting your CYA down to about 70 would be ideal. The exchange will also help to lower the CH a bit which is elevated.

On another note, stop using dry acid. Switch to liquid muriatic acid. Dry acid is bad in the long run for your pool and salt cell.

Your other numbers look very good.

Hope that helps.

 

[Bperry]

the pool was resurfaced just a bit over a year ago, surface and water look great, am just worried about these readings and the main thing right now is that its taking a lot to keep pH levels from going high....am using maybe about 4lbs of dry acid a week....salt level was 3500ppm (its a salt chlorine generator). My pool is in Miami, FL area.
Do i really need to dump half the pool water with replacement?

View attachment 560223

In addition to above, your high TA is why your pH is rising so fast. Get it down to 50/60 and the pH rise should slow way down.

And x2 on the dry acid.

 

[Jimrahbe]

99,

Since you have a Saltwater pool, the question is why is your CYA so high???

What are you adding that adds CYA?

Are you routinely adding Pool Store Shock packages, or Chlorine tablets???

With a CYA of over 100, your FC is too low. You never want to run at the very minimum, you want to try to stay in your target range of 7-13.. If this were my pool, I'd be shooting for an FC of 10 ppm.

X3 on not using dry acid..

Thanks,

Jim R.

 

[pjt]

Why is your CH so high? Have you added anything that adds calcium? What's the CH and TA of your fill water? Miami gets 62" of rainfall every year, so this is puzzling.

 

[imrj99]

Yea I am not sure why CYA got so high.....so the pool store told me to stop using liquid muriatic acid because it will then kill my TA....(which I was doing before), they told me to use pH down powder, am assuming thats the same thing as dry acid?

Adding new water is a PITA for me, as I dont have city water. I have to pump it raw from well and then chemically treat it in the pool (which I did for initial fill 1+ year ago).....I cant use the house water system to fill the pool, is too much.....

 

[Bperry]

Yea I am not sure why CYA got so high.....so the pool store told me to stop using liquid muriatic acid because it will then kill my TA....(which I was doing before), they told me to use pH down powder, am assuming thats the same thing as dry acid?

Adding new water is a PITA for me, as I dont have city water. I have to pump it raw from well and then chemically treat it in the pool (which I did for initial fill 1+ year ago).....I cant use the house water system to fill the pool, is too much.....

Pool store advice….ugh. Muriatic acid will lower the TA a little bit which is fine as long as the TA stays above 50ppm. If it goes below, you can add some baking soda to bump it back up. That will almost never occur though.

pH down is the same as dry acid.

 

[HermanTX]

Yea I am not sure why CYA got so high.....so the pool store told me to stop using liquid muriatic acid because it will then kill my TA....(which I was doing before), they told me to use pH down powder, am assuming thats the same thing as dry acid?

Adding new water is a PITA for me, as I dont have city water. I have to pump it raw from well and then chemically treat it in the pool (which I did for initial fill 1+ year ago).....I cant use the house water system to fill the pool, is too much.....

With both high CYA and CH you will need to drain water to reduce both. It is not ideal based on your situation with water supply.
CYA only increases if you add it because fresh water has no CYA. Did you add chlorine pucks which have CYA in them?

Have you used cal-hypo shock? That will increase the CH in the pool.

Dry acid is not good for your SWCG. Only use MA to lower pH & TA. Use Pool Math app for additions.

 

[imrj99]

So i checked my well water and it does have high Calcium, so maybe the CH is from that?

I took another measurement yesterday, as we got a lot of rain over weekend and I also boosted the chlorine output
I since have added a half gallon of acid, i know the pool store had me add chlorine stabilizer a few times, could CYA come from that? I've never shocked the pool or used any tablets...

I guess if I drain and add water I am going to have to filter the CA from the well water somehow.....(because there is no CA after it runs thru my home water system)

 

[Jimrahbe]

i know the pool store had me add chlorine stabilizer a few times, could CYA come from that?

99,

Stabilizer is just another name for CYA...

You need to quit using Pool $tore advice...

Thanks,

Jim R.

 

[pjt]

So i checked my well water and it does have high Calcium, so maybe the CH is from that?

Use a recommended test kit to measure the CH of your fill water and post it.

You get lots of rain in Miami, so we need to find the root cause of your high CH.

 

[HermanTX]

I since have added a half gallon of acid, i know the pool store had me add chlorine stabilizer a few times, could CYA come from that? I've never shocked the pool or used any tablets.

CYA is called stabilizer. Pool store should have guided you not to over do it. We recommend if you need to increase CYA (or CH) to only add 80% of what PoolMath app states. Let it mix for a day then retest to see the level. This way it avoids overshooting your target.
Adding a half gallon of acid was a lot. Was it 31.45%. If so, then according to the PM app for 12k gals pool volume, that would lower your pH by 1.3 and lower TA by 21ppm. The goal is to slowly lower TA over time and maintain pH between 7.2 and 8.0 after each dose.

 

[HermanTX]

I guess if I drain and add water I am going to have to filter the CA from the well water somehow.....(because there is no CA after it runs thru my home water system)

You can purchase a smaller RV type water softener. I use a whole house water softener but my incoming CH is below 200ppm. yours appears to be much higher. Have you tested the well water as it was stated it is just higher in CH. It is good to have a value to understand your situation.
I think it was stated it is not economical to fill your pool with municipal water supply. Are you able to truck water in?
Based on your CH value of the well water, fill the pool half way with that and then use municipal water for top off.