In what order to add chemicals, and how to do it safely?

[Elle W]

Problem: I'm new to pool care and have a newly replastered 7k-gallon pool. We started up with muriatic acid about 5 weeks ago. The pool company told us not to add any other chemicals until the pH stabilizes. It's still getting high, so we keep adding acid, but it also started to grow algae, so a couple days ago I shocked it, and now want to add the rest of the chemicals anyway. Questions regarding how to add chemicals:
1) do I add the 1" chlorine tablets into a dry floating dispenser, then drop the dispenser into the pool, or do I submerge the dispenser first and then add the tablets?
2) can I add CYA and chlorine at the same time, and if not, which goes in first, and how long to wait before adding the other?
3) how long to wait after adding muriatic acid before adding chlorine and/or cya, and should the floating chlorine dispenser be removed from the pool when adding acid?
4) I put in a pound of shock into the pool 2 days ago, and now TC and FC are back to zero (but it killed the algae and made the water pretty again). Should I shock again, or just add the normal chlorine?
5) TA is low right now, can I add baking soda along with the chlorine and/or cya, or do they needed to be added separately, and how long to wait in between?
6) Any other chemical safety issues to be aware of, besides the obvious (don't ingest or get it in eyes, I wear gloves and goggles when handling dangerous chemicals)

Thanks in advance to anyone who can help.

FC: very low
TC: very low
pH: 6.5 (was 8.0 this morning - added too much muriatic acid oops)
TA: 40
CH: 250
CYA: 0

My pool: 7,000 gallon in ground plaster pool with waterfall spa
Pool chemicals: only muriatic acid and shock so far
My pump & filter: 48sqft hayward DE filter
Other info: We live in the desert, it's hot and dry and windy and dusty - pool gets dirty easily

[Teapot]

Ok, I believe the advice you have been given is very wrong. On a freshly plastered pool the surface has to cure before the pH will stabilise. The best way to do this is to load up the TA level with lots of bicarbonate of soda. This creates calcium hydroxide which forms a tough and pH stable surface. Adding acid will just keep on softening the plaster surface so it will not cure.

By all means add chlorine, I would use the 3" tabs and the dichlor version to add the extra CYA you need. If you have CYA in granular form use it but after the bicarb has been added and fully dissolved into solution which can take several days. You will have to waste some of the water as the TA will be high 250-300ppm.
For more expert advice I suggest getting hold of Kim Skinner the US's foremost expert on plaster surfaces.

[Elle W]

Thank you for your help. I just added two pounds of sodium bicarbonate (it was all that I had), which should raise the TA about 30ppm by my estimate, and I put the 1" chlorine tabs in the dispenser (again, this is what I have for now, and can't run out to the store easily with small kids at home). I have granular CYA, will add that in a couple days. I also have a 121oz jug of walmart store brand 6% bleach, could I go ahead and add that later this afternoon to increase the chlorine levels faster, or will it dissipate too quickly without CYA?

[Teapot]

Hi Elle,
Yes appreciate you can't just run to the store, I would add the chlorine after sun down, it will last longer that way. Most pools in full sun the chlorine lasts around 2 hours without CYA.

[Elle W]

Thank you!