Ben,
We haven't seen a CYA result. I know CYA should not be used in indoor pools, but drdamour put in some sort of powdered chlorine. If it wasn't cal-hypo....there's now a CYA presence...

More Chlorine Math:
FC desired (in ppm) = (1,000,000/pool gallons) * (.06) * num gallons. Since your pool is 5,000 gallons, and you want an FC increase of 3ppm, that's 1/4 gallon. .06 is the concentration of 6% bleach (6%=.06)
I can do THAT in my head since I know that 1 gallon of 6% adds 6ppm to 10,000 gallons. Since you have half that, 1/2 gallon gets the same 6ppm increase. Since you only want half of 6ppm, that's 1/4 gallon=1 quart of bleach.

Carl