I'm not sure how to interpret your HTH test results. pH at 7.5 is good. FC "about" 6-10? With a DPD powder and FAS drop kit there isn't any 'about'. I have never used an HTH kit and so I can't really question or discuss the results.

Wild guess? Add 1 quart chlorine at night, test in the morning. If you're between 3 and 6 ppm FC, you're good. If you're below 3 ppm, add 1/2 gallon, instead. The chlorine demand changes depending on how much the pool is used.