Order to add chemicals before SLAM

[ba67]

I just opened our pool after waiting 2 weeks for a new sand filter to be installed. (A critter of some kind chewed our drain pipe ). CYA is zero at opening and water is extremely green so I know this isn’t going to be an easy SLAM. Here are my water chemistry results the morning after running the pump all night:
FC - 0
CC - 2
TA - 40
PH - 7.0
CYA - 0
I plan to add a gallon of liquid conditioner which will get CYA up to around 20 and add 4 lbs of Dichlor to get CYA to 30 since I already have this on hand. I need to know what I need to add before adding the liquid conditioner and how long to wait after adding each thing. I’ve never had to add so many chemicals at opening before so any advice would be appreciated.

 

[MITBeta]

I would add about 1.5 lbs of washing soda to raise TA and pH a bit, especially since the CYA and dichlor are acidic. You can add everything: CYA, dichlor, and washing soda in pretty quick succession, and then SLAM on.

 

[splashpad]

I just opened our pool after waiting 2 weeks for a new sand filter to be installed. (A critter of some kind chewed our drain pipe ). CYA is zero at opening and water is extremely green so I know this isn’t going to be an easy SLAM. Here are my water chemistry results the morning after running the pump all night:
FC - 0
CC - 2
TA - 40
PH - 7.0
CYA - 0
I plan to add a gallon of liquid conditioner which will get CYA up to around 20 and add 4 lbs of Dichlor to get CYA to 30 since I already have this on hand. I need to know what I need to add before adding the liquid conditioner and how long to wait after adding each thing. I’ve never had to add so many chemicals at opening before so any advice would be appreciated.

Wait on the conditioner, the CC/2 is slightly concerning with green water. I do agree to raise your TA to at least 50, 60 is preferred minimum for fiberglass.

When you add chlorine, does it register (testable) or immediately dissipate/oxidize (non-detectable)?

 

[ba67]

Wait on the conditioner, the CC/2 is slightly concerning with green water. I do agree to raise your TA to at least 50, 60 is preferred minimum for fiberglass.

When you add chlorine, does it register (testable) or immediately dissipate/oxidize (non-detectable

Wait on the conditioner, the CC/2 is slightly concerning with green water. I do agree to raise your TA to at least 50, 60 is preferred minimum for fiberglass.

When you add chlorine, does it register (testable) or immediately dissipate/oxidize (non-detectable)

Wait on the conditioner, the CC/2 is slightly concerning with green water. I do agree to raise your TA to at least 50, 60 is preferred minimum for fiberglass.

When you add chlorine, does it register (testable) or immediately dissipate/oxidize (non-detectable)?

FC went from 10 ppm to 1 ppm in an hour so FC isn’t lasting long. If a TA of 60 is preferable for fiberglass, would it make more sense to increase TA with baking soda instead of washing soda so PH doesn’t get too high since liquid chlorine increases PH? Could I add the 2 lbs of baking soda that I already have to increase TA to 48 and then add only a pound of washing soda which will get TA to 54 and PH to 7.2? I’d like to get rid of this big box of baking soda if it won’t complicate things to add both washing soda and baking soda. I also need to know how long to wait after adding these chemicals before I can add the liquid stabilizer and chlorine. I think I’m going to start the SLAM with liquid chlorine and save the Dichlor for tomorrow.

 

[MITBeta]

Keep adding 10ppm of chlorine at a time and testing 15 minutes later until you can hold 5ppm or better. Then start adding CYA.

I recommended the washing soda because it will raise TA and pH, which the acid you're adding will push down some. Baking soda won't hurt, but won't raise pH directly.

Liquid chlorine doesn't raise pH on a net basis. It raises when you add it, but returns to where you started as it breaks down back into salt.

 

[duraleigh]

Would it make more sense to increase TA with baking soda instead of washing soda

Absolutely. Baking soda would be my first choice anytime.

 

[ba67]

Absolutely. Baking soda would be my first choice anytime.

If I use up the 2 lb box of baking soda I have, it will get TA to 48 and PH will still be 7.0 according to pool math. Is there is any harm in adding 1 lb of soda ash to increase PH to 7.2 and increase TA to 54 according to pool math? If so, how long should I wait after adding the baking soda to add the washing soda? I’ve got to go to the store to buy something to increase the PH and increase the TA further and washing soda is pretty cheap.

 

[splashpad]

FC went from 10 ppm to 1 ppm in an hour so FC isn’t lasting long. If a TA of 60 is preferable for fiberglass, would it make more sense to increase TA with baking soda instead of washing soda so PH doesn’t get too high since liquid chlorine increases PH? Could I add the 2 lbs of baking soda that I already have to increase TA to 48 and then add only a pound of washing soda which will get TA to 54 and PH to 7.2? ...

Absolutely use what you have to raise the TA, PH will come up "naturally" with increased TA.

... I also need to know how long to wait after adding these chemicals before I can add the liquid stabilizer and chlorine. ...

You need to get your TA & PH good before increasing chlorine levels, as elevated chlorine levels interfere with other test reagents.... that being said; Keep adding 10ppm FC for your pool according to poolmath, until it holds as instructed above, then add stabilizer/conditioner to reach CYA/30ppm (it's easy to overshoot, so better to go slow)

... I think I’m going to start the SLAM with liquid chlorine and save the Dichlor for tomorrow.

You will want to use LC (liquid chlorine) for the SLAM after your other levels are stabilized, so that you don't keep increasing CYA