The pool store provided my results which I have attached. I'm concerned about the high tds at 3800 which they told me to remove and refill water but looking at precious threads seems like that I should not be concerned? I have approximately a 15,000 gallon plaster pool. They said I have a high pH 8 1 and low cya at 12. I just don't know what to do first. Also have yellow mustard algae growth which I have removed from walls but now Want to start the process of balancing my pool but again don't know in what order. Also do I shock the pool after?