With a cya of 60 you should have your chlorine at a minimum of 5ppms. With an alkalinity of 50, calcium at 150 and ph at 7.4, your pool is slightly acidic. I would bump the alk up with baking soda, as traceyb said, and it should take your ph up slightly also. If you have a vinyl liner you don't need calcium, but if you have a plaster pool you will have to take your calcium up to 250.