Just to reiterate what Watermom said -- you are giving us widely varying test results from a variety of unreliable test methods. 'Guess-strips' aren't always wrong, but they are always unreliable. Cheap OTO chlorine test are very reliable, but not very accurate. Phenol red drop tests may or may not be reliable, depending on the chlorine reading.

Without reliable test results, we can't help you, because we can't come test your pool for you. And, unfortunately pool store test results ARE NOT reliable. (A very few pool store -- maybe 2 - 3% -- are reliable, but the only way to determine that is by comparing your ACCURATE results with theirs.)