New pool, high CYA on well

[bradthebold]

Hi, we just moved into our new house this weekend and uncovered the gunite pool. 2 months ago we had it inspected and they noted a pH of 7.5 and Cl of 10 and apparently that's all they tested. Today, with a TF-100 kit, I got:
7.5 pH
1.5 FC
0.5 CC
300-325 CH
110 TA
>100 CYA (~1/8" over)

We are on well water that has "some" iron that I still need to test. The house has a water softening system, would need to check if it goes to the outside faucets. What are my options of using the pool this year? Hire someone to drain and bring water if that's even an option? Test my water and hopefully fill in a couple weeks, possibly needing some other kind of filtration? Can I just drain it the pool into the yard/field with a submersible pump? What would potential costs be? It could use an acid washing, and the pool company that did the inspection said it would be about $700 I think, so depending on other costs and if that includes dealing with the water, that might be an ok option.

What should I do about chlorine in the meantime, try to keep it up around 12? Just abandon it and put the safety cover back on until it's dealt with? It's a disappointing discovery when hoping to use it next week.

 

[mknauss]

100 is the limit of the CYA test, so you have to do a diluted test. Mix 50% pool water with 50% tap water. Use this mixed sample as your test water. Multiply the result by 2 for your CYA level.

At that point, you can see if you want to try and manage the pool with the high CYA or explore other options.

Why an acid wash? Is there scale buildup?

 

[bradthebold]

Ok, I will try that tomorrow.

I don't want to maintain it that high though, so I definitely want to figure out the best way to replace at least some water.

The bottom of the pool just looks stained/dirty and the pool company recommended an acid washing.

At least for now, we decided to put 3 gallons of bleach in to get us close to 12 FC, though it may be low if my CYA test was off. And we left the safety cover off and put a solar cover on. I'll check CYA and FC again tomorrow.

 

[mknauss]

Stained/dirty plaster does not warrant an acid wash.

Once you get things settled, post some pictures of the pool. Stains are either metal or organic. It is possible to address both without an acid wash.

 

[bradthebold]

As far as the dirty look, it was actually dirt. What I thought was stain brushed away, so I will re-evaluate after the vacuum gets here. I'm not sure what the pool company was talking about then, there does not appear to be any mineral build up I notice at least.

I retested CYA and I'm not 100% sure what the black dot disappearing point is. It was hard to see at 90, but was not noticeable at all at 50-60. So doubling that, I'm guessing it's close to 110-120, though it could be higher. FC was 11.5 today and CC 0. I guess until I figure out a water replacement method and do some testing, I will just maintain FC around 12-15. There doesn't seem to be any negative to it, except that it took more chlorine to get there? It should take the same amount to maintain at 14 v 4? As long as I keep it up and don't need to SLAM.

 

[mknauss]

It should take the same amount to maintain at 14 v 4?

Might take a little more. But better that than letting the pool turn to algae on you.

 

[bradthebold]

After several brushings and vacuumings, this is what the staining looks like. It's the worst along the wall/floor junction and scattered on the floor.

 

[mknauss]

Looks more like plaster mottling than stains. Is there a color to them?

 

[bradthebold]

Just a dirty grey color. Looking up plaster mottling, that's what it looks like. And it looks like resurfacing is the only solution, so I guess I'll just live with it. The amount of threads of this happening within months of replastering is concerning too if you're hoping for that to fix the issue.

 

[mknauss]

Has alot to do with color of plaster (darker is an issue) and technique of the plaster personnel.