new pool (new to me, but it's probably 10 yrs old) and i opened it 2 weeks ago. i have repeatedly shocked it, way beyond the recommended dosage, and put 1, 2, and finally 3 simultaneous floating chlorine dispensers full of chlorine, and fully open. it's only a 5000 gal pool and yet the chlorine level remains around 0.
what am i doing wrong and how can i get the chlorine level up? every other chemical is perfect, including cya (or whatever the chemical to stabilize chlorine is called).