Fastest way to lower alkalinity; empty a bit and then refill?

[jkarn]

Hi all,
I have a 1600gal IG FG spa with chlorine sanitizer (trichlor). I just opened late last week. This is my second year with my pool/spa and I believe I misunderstood the impact baking soda has on ph and alkalinity resulting in an extremely high alkalinity (was at 310ppm yesterday). I got it down to 290 by adding ph minus about every hour and testing again, but I know this is going to take a lot of effort and $ if I don't come up with a better solution. I've already added almost 2 lbs of acid with little effect. Would I be better off just pumping out some of the water and refilling? Is there a way to calculator about how much water I'd need to pump out?

 

[Texas Splash]

You can change water if that's easier and cheaper for you. You should avoid that pH Down stuff. Dry acid is not only more expensive but has side effects over time (sulfates). You should use muriatic acid. Lower the pH from 8.0 to 7.0 and you will see the TA start to fall much faster. But for now, if a water exchange is easier on you, do what's best.

 

[duraleigh]

A 1600 spa probably cost about $15.00 to refill. I would dump it and start over.