An Introduction to My Pool - Old Plaster - Old Pool - Black Algae !

  • I have 3 hoses available to fill the pool with
Skip the rags.
  • Fill water chemistry as of today is as below - Any special considerations considering these #s? Do I need to attempt chemistry modification while filling for the pH?
    • pH over 8 - 5 Drops to bring down to 7.4 - Does this need to be managed during fill?
No, get it filled, then follow the NPC guide.
    • CH - 112 - This is over range per the sheet - Not sure how to bring down or if too high?
Don't worry about it.
    • Total Alkalinity - 95 - The muriatic acid required to get the pH in range should take care of this.
Yep
    • Balance chemistry as per the daily program
Yep
  • Run pump 24/7
    • presumably backwashing pretty regular.
Yep
  • Once full I will retest and test for metals
    • Sample to Pool store for the metals - to save money on kits
    • What are opinions on sequestrants for Step 7.
I wouldn't even test.
Use Jack's Magic the blue stuff.
  • Brush pool 2 times a day for the 1st 7 days.
    • No wheeled vacuums for 28 days
    • Need to get a brushed vacuum
Yep
  • Day 4 says to begin adjusting CYA to 30 to 50 ppm
    • Its worded strangely.
      • Do i add 10 ppm per day for 3 days to get to 30?
Just add it using the sock method. Hang in front of a return. Keep it at least a foot away, two would be better, from the plaster. If it takes a couple of rounds to get all the CYA up to 30-50, that is fine. Strange wording, but it just takes time for CYA to dissolve, that resolves your strange wording. Do not add to skimmer.
  • Do I follow Day 1 route for CH here brining up 10 ppm at a time waiting several hours between each?
You need to add about 100. Add 25ppm 4 times over the day.
  • The Orenda App has me covered for the LSI calculation
  • Pool Math for everything else
Great. I would just do it all in pool math. Do not get hung up on the "which is better" or "right" debate, as that is a false choice. The indices are simply measures of how stable calcium carbonate is in solution. You can use one or the other; both will give you the same general answer.
 
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My buddy who is a contractor called me concerned about hand mixing for the plaster install. Is this an issue to be concerned with?
Hand mixing plaster? For a small repair maybe ok, but depends on what hand mixing actually means. Big jobs use a large machine (ie cement mixer) or at least a very large handheld mixing drill type device.
 

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You can get a test kit, LaMotte sells a Sequestrant Test Kit (Part No. 4064-01).
Per the NPC card, it indicates just to follow the sequestrant manufacturers instructions.
Up to you.
We at TFP like to test and know what and why we are adding it. For a 30$ test kit vs 1000s of dollars for the pool...🤷‍♂️

I would not continue the use of sequestrant after the 30 day startup. Sequestrant during startup is just insurance for metal stains, that are hard to remove, if you get them during startup.
 
@PoolStored

So far so good on day 2 following NPC program to a T + Jacks Magic Blue.

On the NPC instructions. Day 4-7 says repeat Day 2 step 2 to adjust calcium hardness, which makes no sense to me. Should this be Day 3 step 2 to add the liquid chlorine? Is this a typo?

On brushing i am noticing no particulates, water is very clear, but has a green tint a little less so today than yesterday. My question is would this be a bloom or is the discoloration likely coming from something in the plaster. Is the no plaster particulates normal. Is green tint normal?
 
On the NPC instructions. Day 4-7 says repeat Day 2 step 2 to adjust calcium hardness, which makes no sense to me. Should this be Day 3 step 2 to add the liquid chlorine? Is this a typo?
That is not what it says. It says adjust pH and TA maintaining the ranges from Day 2.

1745610406426.png

Then it also says on Day 4 to raise CH from the 80-100 from day 1 to 200 on day 4.
1745610445819.png
 
@PoolStored
So far so good with the start up program. Day 5

  • Cya <30 added 2.5 lbs to the sock so it should be approaching 25. Im gonna run tabs to get it the rest of the way if there is no issue with that.
  • CL - .5 ---> 3 with liquid this AM
    • I dropped 2 tabs in the floater this morning so it stops going to 0 in between rounds
      • Is this Kosher?
  • CH - 300 headed to 350
    • will mix another 10 lbs or so to get there today
  • ALK steady at 80+
  • pH - 7.6 pretty steady

  • Given the above is it ok to go ahead and install the pool light. I read that I should wait 28 days on that, but the plaster guy is coming to put that in today??
  • Also i noticed this black spot appear about a foot below the tile in one spot. It feels like aggragate, i tried to brush it out as I was worried about black algae since my CL kept going to 0 periodically using the Liquid CL.
    • Is this just an errant piece of non quartz aggregate?
    • Brushing sort of created a little grayish swirl around the spot?
      • Should I be worried here?
      • Plater guy is supposed to be here today with the light so I will ask him then.

20250427_143836.jpg
 

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