TA reduction going wrong ??

[PoolDoc]

Do NOT add any more acid!!!!

However if your pH is 7.0 or above, you don't have to try to raise it, either.

There's no need to raise your pH for your SWCG, but you don't have to try to lower it, either, once it begins to go up.

I wasn't clear on what you were saying -- did you lose all your CYA over the winter, or not? Did the brown scale go away?

Notes:
+ Cal hypo does NOT raise CYA. Calcium, yes. But not CYA. You don't want to use a lot of that, on a pool with an SWCG.
+ High CYA is not a necessity, but it lowers chlorine usage and extends your SWCG life.
+ Don't trust that Taylor booklet much -- it's the worst thing about that kit.

[Heavyhook]

I did loose all my CYA during the 7 months the cover was on my pool. I had about 15 pounds of HTH Calcium Hypochlorite tabs left over from when I switched to the BBB method 2 years ago. I thought it would be a good opportunity to use Calcium Hypochlorite tabs up since my testing showed my CYA had disappeared. My last test 3 days ago show CYA back up to @ 30 ppm. I am almost out of tabs so I will have to use CYA powder/granules to raise it the rest of the way to 80ppm I read on this forum is recommended for SWCG systems.
I still have the brown scalling on my liner. I was reading some info on metals in the water causing this problem! Then I remember finding my alluminum pole that I attaché my brush head and net too for cleaning the pool on top of the cover late last winter. The blue anodized coating on the pole had disappeared and the pole had a some what oxidized look to the aluminum that the pole was made of! Just a thought.
After following the Taylor K2005c test kits instruction on lowering the TA I have made 3 of the 4 days acid treatments so far or about 90 % of the total acid they recommend to make my correction. I will not add the last dose tomorrow. After reading this evening the procedure recommended on pool forum I started aerating my pool. What do you recommend from here? Thanks for your help !!

[Watermom]

I think you may have missed what Ben stated in his post above. Cal-hypo does NOT add CYA.

[Heavyhook]

Watermom, thanks for ringing in on my post!
I had to go back and take a 2nd look @ the containers my chlorine tabs came in. When I first purchased the home 2 years ago I inherited my Doughboy pool. My pool had originally been on bromine for sanitation. I drained and refilled my pool and started using Trichlor-triazineirione tabs after that. Some where along the way I had purchased 15 pounds on Cal-Hypo. I had quit using all the tabs when my CYA reached 50ppm and switched to the BBB method.
I installed a cover for the first time last November and I pulled my cover off in the middle of July, add when I tested the water I found the CYA was gone. I ran the CYA test 3 time and same results, O ppm CYA. I thought I would use the tabs I had left over from two years ago to reintroduce CYA into my water. I have used about 6 pounds of Tri-Chlor I had left and the started using the Cal-hypo. Sorry for the confusion. I assumed wrongly both types of tabs contained CYA.
Anyway when I used up the Tri-Chlor I had about 4 days ago and my test @ that time showed 30ppm CYA. I started aerating last evening and checked my PH and TA again @ 2:00pm central time. My latest test show PH 7.6 and TA 100ppm . At this point do I need to add CYA powder/granules to 80ppm before I start my SWCG for the first time?
I do still have brown scaling on the bottom of my liner where it makes the transition to the wall. This showed up after last winter with a cover on or the first time? I have read on the Forum about possibly some metal getting into the water? Any ideas about that? Thanks again !!!

[PoolDoc]

I'm a little confused.

Could you list -- just a single list -- of your most recent COMPLETE chemical tests: FC, pH, TA, CH & CYA?

By the way, I took your test values OUT of your signature; those values will change, and leaving them in your signature could mislead someone into giving you wrong advice. And, as it is, I wasn't clear on what the date of those values was.

[Heavyhook]

Here are my test results as of 7:00pm central time today.

FC: 2.0 ppm
CC: 0 ppm
pH: 7.8
TA: 100 ppm
CH: 90 ppm
CYA: 50 ppm
Borates: 30 ppm
Temp - water: 80F, air: 95F

Pool had just been covered with shade for the day!
Thanks

[PoolDoc]

OK, thanks.

Now, what are your current questions? I'm guessing they are:

1. How do I remove the scale?
2. Do I need to do anything else?

I'll answer those two, in any case:

1. Lowering your pH to 7.0 and keeping it there will cause your TA to drop, slowly. Low pH and low TA will maximize your chance of removing the stain / scale.
2. I would recommend testing the stain / scale to see what will remove it. You can do so by holding various chemicals against the stain / scale for a couple of minutes. I'd recommend testing in this order:

1. Vitamin C tablets
2. Dichlor or cal hypo granular chlorine.
3. Iron Out powder
4. Sodium bisulfate (pH Down aka dry acid)

You should wear plastic gloves, and put the chemicals in #2 - #4 in a old (but clean) wash rag.