Hi there. We are the new proud owners of a 10' x 18' 4,000 gallon pebble tec spa. I have been trying to get it balanced over the past two weeks and have made no headway. I finally got my alkalinity to 110 and was then trying to adjust my pH which continued to be very high (7.8-off the chart) and of course now after adding a ton of muriatic acid to get it down to a pH of 7.8, my alkalinity is down to 50 ppm. Of course with my pH so high my chlorine has been a nightmare to try to keep even in the 1-2 range. So now I am at a TA: 50 ppm, pH: 7.8, free Cl: 0. I've been testing it every 12-24 hours and trying to adjust it. I feel like adding as much sodium bicarb as I did to get the TA within the right range that my PH went sky high and I've been struggling (with muriatic acid) to bring it down over the last week. I understand that adding muriatic acid is going to bring my TA down as it brings down the pH so I don't know where to go from here. I also understand that beyond causing scaling in the spa/filters/pumps, that a high pH eats up the chlorine in the spa so that it's not available to sanitize. So, I'd be so very grateful for any help with what to do. The people who put in our spa suggested getting our TA to 110-120 and a pH of 7.3-7.4 to get our saturation into the right range. They suggest testing it once a day at most...I'm just nervous and want to get our spa balanced as soon as possible so that it is sanitizing and not starting to cause scaling.