I supposed this could be caused by conditions other than the poor quality salt.
- Metals (high iron) in the water reacting to the salt.
- Salt that is old or exposed to moisture.
- Vitamins or additives added to salt by manufacturer at to high a ratio.
- Tainted salt mix. Some additives turn water yellow when dosing, perhaps the salt was exposed.
I used a RODI system with 3 DI sections. Salt is never old unless its old when it ships to me. So I dont know