Start-up with Quartzscape

[zz28zz]

Just had our 30k gallon in ground pool re-plastered using Quartzscape.
We filled the pool yesterday and I started the pump last night. Today I brushed it, back washed and recharged the DE.
Also added some stuff (forgot what it's called) to prevent any metal staining from the fill water.

The guy that did the re-plaster was asking me what kind of start-up I wanted.
I've been researching this for almost 24 hrs and my eyes are bleeding.
Hoping someone has experience with this type of plaster and knows what's best.

I'm leaning towards the acid start-up since it's supposed to expose the quartz and make it look nice, but I'm concerned the acid may compromise the overall integrity and service life.

Gotta make a decision pretty quick.

I'd like to start using the pool ASAP since this project was started in April and I'm quickly running out of summer.

Thx in adv
JC

[CarlD]

Hi!
It's a little concerning when the installer does not have a recommendation for the start up and curing period.
Why did you add something to prevent metal staining? Do you know for a fact you have a high concentration of copper or iron in your water? Our approach is generally do NOT add something hoping it will fix a problem you don't know you have.

Beyond that, I'll let our experts on hard-side pools comment.

[zz28zz]

Hey Carl;
We filled pool from a fire hydrant since the house is on a low capacity well. We apparently didn't flush the hydrant very well cause the water looked like it had something in it, I'm assuming it was rust. The water cleared up after a few mins but the deep end looked a bit murky. After running the pump for abt 18 hrs, it cleared-up considerably but I was worried abt the rust staining the new plaster/quartzscape.

I spoke to the plaster installer (he claims he is not a "start-up guy) and he's saying we need to add 4 gals per 10k gallons, so looks like we need to add 12 gallons of acid. Seems a bit excessive. I can't find a test kit locally that reads Ph values in the 5-6 range. After adding the metal sequestering agent I added 1 gal of acid. Abt 1 hr after that, the Ph was at 7.2...

[zz28zz]

Picked up a Taylor test kit today. Here's the results: (I have not added any chlorine)
Free chlorine= 0
Total chlorine= 2
Combined chlorine= 2
Ph= 7.8
Acid demand= 3 drops
Alkalinity= 140
Calcium hardness= 120
Pool temp= 82
CYA= <30
Saturation index= +0.15

Spoke to the installer again today. Now he's saying 1 gallon of acid for each 4,000 gals of water.
That sounded a little better than 4 gals acid per 10k gallons of water.
Shut off pump (lights are already out of water) and added 7 gallons of acid (pre-diluted). Swept pool again to help mix up acid.

Will leave Ph there for 48 hrs, then dump ~ 50 lbs of soda ash and see where I'm at. I'm assuming once the chems are back in balance, I can jump in. Anyone see any red flags??

[CarlD]

I would chlorinate with Cal-Hypo powder, to get your CH over 200 and raise your FC--catch it now before it becomes a problem and you grow algae! add stabilizer(CYA powder or liquid), and don't worry about Alkalinity--it will drop with all the Muriatic Acid you put it. But be prepared to add Borax to raise your pH back to where it should be.

[zz28zz]

Thx Carl.
I wasn't sure abt chlorinating with such a low Ph so I held off. I assume the Cal-Hypo powder needs to be dissolved with water before going in the pool. From what I heard, the plaster is especially susceptible to chems while it's curing. In regards to bringing the Ph back up, is borax better than soda ash. If so why? Roughly how much borax would I need?

Thx for the reply. I need the input.
JC

[BigDave]

Soda Ash will raise pH and Alkalinity. Borax has a much smaller effect on Alkalinity - TA of 140 is fine.

CarlD is right, you need chlorine and calcium.

[zz28zz]

Playing with the pool calculator I was able to determine approx what pH my pool is currently at by knowing the pre pH, amount of acid introduced and the pool capacity. Looks like I will need approx 17 lbs of borax.

In regards to CH, my pool was filled with soft city water, but will be maintained with very hard well water. Should I try to keep the CH as low as I can get away with? Seems like it will only climb over time. In the past, I have had major scaling issues and pH is constantly need to be lowered. In the summer I add 1 gal of acid every 2 weeks. I did have a small leak at the pump until just recently, so that explains some of it.

[BigDave]

Don't add all that borax at once, you don't want to overshoot. pH change is very difficult to calculate and non-linear. Add a couple boxes, let it mix for a couple hours, measure pH, dose half as much, ... repeat as necessary. It's fine if you want to use the calc as a range for purchasing the borax. You can add borax s-l-o-w-l-y through the skimmer, it will form a hard plug if you add it too fast. Break up any chunks as you go.

The water will leech calcium from your new plaster, I'd get CH up to at least 200.

[CarlD]

As BD said, you need at least 200ppm of CH. To answer your question that is the lowest CH you "can get away with".

BD is also telling you a basic rule of ours: Always add LESS than you think you need because you can always add more.

Except for chlorine. Too little is always trouble. Too much rarely is.