And just to make sure that it doesn't get missed in the ton of information you're trying to process right now, don't worry about the washing soda--with the numbers you have, you don't need it.

Stay the course that Watermom, Carl, and Polyvue laid out for you---now that your pH is up into the 7.? range, concentrate on the chlorine and clear up the green. Once you do that, you'll find that your numbers are actually pretty good and it will just be a matter of maintenance from there. Keep the filter running, keep brushing daily, backwash as needed when your pressure starts to rise on your filter, keep the chlorine up, and it'll get there!!

Janet