Water Chem for Plaster Break-In Period - PB vs. Pebbletec vs. TFP

[Stoopalini]

Our pool is finally done, and yesterday was the 1st day we got to swim in our pool, and I must say, it was a great success!



I started the day with getting the pH down from 8.2 to 7.2, then added 10% chlorine, and also added 20ppm CYA. I continually checked the levels with my TF-100 kit throughout the day, adding 10% as needed. I logged everything in PoolMath, and enabled sharing, so it is visible on my profile.

I also ran an OCLT last night, just to be sure there wasn't anything hiding in the plumbing, since we had water sitting in the pipes for several weeks, unpressurized (long story, during construction, the caps blew off the skimmers relieving the pressure). The pol maintained 3.5FC overnight, so I think we are good.

My question is about the levels I should be shooting for, during the initial 28-30 days, while the plaster is curing. My PB has their recommendation, Pebbletec (I have Pebblesheen plaster) has their recommendation, and of course TFP also has water chem recommendations.



I only added 20ppm of CYA, because the in-line chlorinator is filled with Trichlor pucks. So my plan is to allow the pucks to raise the CYA, and I'll maintain FC levels with 10% as needed, in addition to the chlorine coming from the Trichlor. Once my CYA reaches target, I'll remove the pucks, and stick with only 10% until we're ready to add salt and turn on the IC40.

One of the guys from the PB was insistent that I needed to immediately drop my TA immediately down to 90 by adding a lot of muriatic acid. I know this will tank my pH into the 5's, and will also lower my CSI down to around -1.7. So I didn't let them do this, and said I would bring it down over time.



But I also know I should be maintaining a slightly positive CSI during the plaster curing. So what is the best way to get the CSI into the slightly positive side?

Should I raise my CH to the TFP recommended 350, which is above the Pebbletec's recommendation? And then maintain a 7.6 pH, which is also above Pebbletec's recommendation?

For TA, it appears 80 is the only target which is common across all 3 methodologies. Although I realize I should not be targeting TA specifically, and don't plan to make chemical additions specifically just to alter TA .. unless, it makes sense to do so in order to bring CSI to slightly positive.

For CH, 200 - 250 is within both the PB and Pebbletec's recommendation, but is well below TFP's recommendation of 350-550.

I guess my question is "what targets should I set for this initial plaster curing phase, to ensure I'm aligned with TFP methodology, while allowing the plaster to cure properly, and not have water chem issues develop in the future?

Using PoolMath to play with the numbers, I think the below would get me to a good place, but would appreciate some input or confirmation on it:

Proposed Targets:

• FC: 3.5
• pH: 7.6 (above Pebbletec's recommendation)
• TA: 100 (above TFP's recommendation)
• CH: 250 (below TFP's recommendation)
• CYA: 20+ (allowing it to rise to 60 using Trichlor pucks)

The above would give me a CSI of +0.16 with 87*F water temp.

Thanks for any input

 

[mknauss]

Your proposed targets look fine. The CH will climb somewhat on its own from fill water, etc. So getting it to 250 and then let ride is fine. That is still within the range on our levels page.

 

[Stoopalini]

Your proposed targets look fine. The CH will climb somewhat on its own from fill water, etc. So getting it to 250 and then let ride is fine. That is still within the range on our levels page.

Thanks for the input ... FWIW, my autofill is connected to my soft water line, so I don't expect the CH to rise from it.

Will maintaining CH of 250 long term cause any issue with following the TFP methodology?

 

[mknauss]

If you will be controlling your CH, then eventually you want to get it near 350 ppm.

 

[CrystalRiver]

If you have a warranty to protect, then you need to be within ranges per whomever is providing the warranty - possibly both PB and Pebbletec - throughout the warranty period. Some also require proof that your levels were kept within range, AKA documented pool store testing. If PB says pH 7.2-7.8 and Pebbletec says 7.0-7.4, then you have to keep it 7.2-7.4 to maintain your warranty coverage from both companies.

Getting CH in range is primarily about controlling CSI, from what I understand. Somewhat similar to TA - the value itself isn't directly very meaningful to your pool, it's more the overall effect it will have over time. Controlling TA is mostly about controlling its influence on pH. Controlling CH is mostly about controlling its influence on CSI.

 

[Stoopalini]

Thanks guys. The warranty is through the pool builder, and the curing targets I outlined above are all within their ranges; so I'm comfortable there.

Give the input here, I made a laminated cheat sheet to stick inside my TF-100 case, so I don't have to keep looking stuff up while I'm learning


Front side:




Back side:



I'm also teaching the wife along the way, so this will help a lot in transitioning from "Pucks+Liquid", to "Liquid Only", then to "SWCG".

So I'll use the "Plaster Curing Targets" column for the 1st 28 days, with FC target based on the CYA climb .. then switch to TFP targets, using the correct CYA row based on liquid or SWCG.

I think I have a solid plan