A 40% water change is huge, but besides the point. Also, I swear the last grains of IO salt are still not dissolved when I dump my new water in my tank. I've never had any problems.
I have however tested my fresh IO make up water just out of curiosity. I got pH 8.2, alk 3.5meq/L, Ca 300 or 350ppm (can't remember now). Alk through the roof is definitely not normal, tested right after mixing or whenever.
I'm not sure about compensation however. Hopefully they'll be really good about it, but you may end up with a fight on your hands to get any sort of compensation other than a replacement of your bad bucket. The 40% water change is only leverage against you if you try to get compensation for your losses. But then again it's not like I've had to contact IO for anything so for all I know it could be smooth sailing dealing with them. Just be prepared.
Good luck! Hope your tank comes back around soon
