I added 12 oz of yellowtrine to my 27000 gal pool to get rid of mustard algae. A week later still no chlorine readings and ive added 10 pounds of Cal Hypo granular chlorine. Pool store tells me i need to keep adding till i break the bearier. Is this correct? ph is good, well just a little low 7.0. alkalinity is good cya is good calcium is good. is it ok to swim? and do i keep adding chlorine? pool is clear right now.