Getting a new pool

[flipflop]

Well, not really a new pool, but starting tomorrow we're draining it, then having the coping and tiling replaced, and the surface re-plastered. So basically a new pool since we'll be refilling it with untreated city water from delivery trucks.

So I'm wondering how best to get the water quickly in balance. I'm very familiar with the TFP methods since I've been following it for over 10 years now, but starting fresh is a new thing for me. I'm considering using stabilized shock for initial chlorination, and adjusting pH as needed. I'll grab a sample as it's filling so I know where I'm at with TA and CH and add baking soda and calcium as it's filling.

For CYA, I'm considering just using dichlor or trichlor pucks or sticks and letting CYA gradually rise until I hit around 40. Does that sound like a good idea, or should I just float socks as it fills?

 

[Msch99]

Personally I would prefer to add stabilizer to be at my desired CYA level in a short period, then I would know how much Chlorine to add daily. Instead of calculating how much the pucks add or testing CYA multiple times.

Why stabilized shock instead of liquid chlorine? Just curious.

 

[Oly]

Double check Pool Math but it looks like you would need 18 trichlor pucks to hit 30ppm CYA for a pool your size. You may be burning through FC until your CYA levels rise above 20ppm.
The stabilized chlorine will also lower your pH but this may be an advantage with new plaster. Going to be a moving target and lots of frequent testing. Watch your CSI closely too.
If this was my situation I would jump start my CYA to 20, get CH into target range then push CYA up to target.

 

[DorsalSpine]

I have refilled due to CYA issues in the past as well as new liners. I'd add the CYA ASAP in either granular or liquid form. I save pucks to tweak CYA values late season and/or in a floater for vacations.

 

[flipflop]

Why stabilized shock instead of liquid chlorine?

Because I'm lazy . I hate mucking about with filling socks, waiting for the stuff to dissolve, etc. But as has been pointed out, the low CYA will keep me chasing good FC levels for a while, so I'll probably go with Oly's suggestion to use stabilizer to get it to 20 early on.

Thanks for the input, everyone!

 

[flipflop]

Update: Pool got re-plastered and refilled yesterday and my test results so far are basically all "LOL!", especially pH which is Off. The. Charts. I'm dealing with all that, but now I have a question around calcium hardness.

CH last night was 50, and had risen to 80 by this morning. My question is, should I bother adding calcium while the fresh plaster is leaching CH into the water? Or should go ahead and add calcium to prevent the water from sucking so much calcium out of the plaster?

 

[mknauss]

What start up process are you using? Plaster company should have provided one.
Read Plaster Start-Up Guides - Further Reading

 

[flipflop]

Plaster company should have provided one.

All they did before they left was give me two bottles of a cleaning agent to add to the water once the pool was filled. They also said to avoid using the steps for five days. Not sure why we can use the pool but not the steps, but it'll probably be at least a few days before I'm happy with the chemistry before getting in the pool, anyway.

EDIT: It wasn't a cleaning agent they gave me...it was a sequestrant.

 

[mknauss]

Read the guides I posted and see which one fits the best.

 

[flipflop]

Read the guides I posted and see which one fits the best.

At one of those links, I saw this bit:

The CSI is not applicable to new plaster finishes under 30 days old. It is actually necessary, to achieve a smooth and dense surface, to have about a +0.5 CSI during the first 30 days. This is because the plaster (cement paste) surface contains about 20% calcium hydroxide, which is somewhat soluble in balanced and slightly positive CSI water and can be dissolved away. The plaster surface needs to be "carbonated" before the CSI should be lowered to the acceptable and balanced range. And that generally is achieved during the first month under balanced water.

My CSI right now is +.47 (close enough to .5, I guess), but what do I need to do to keep it around that range for the next 30 days?

 

[mknauss]

Calcium Saturation Index (CSI)

How is CSI calculated? Very simple – use our PoolMath tool. To ensure long plaster life and save money, click here to learn more.

www.troublefreepool.com

CSI is primarily driven by pH, TA, and CH. Salt, CYA, Borates, temperature, also have contributing factors.

Mess with Poolmath with your conditions and see what effects CSI for you. Your CH being low will be an issue. I suspect you should add some calcium, but not go crazy as your new plaster will be adding some as well to the water.