THIS IS NOT SAFE TO USE
I don't care what the label says. It will dissolve pumps or copper, not sure which. In less than 3 mins of cycling water through my tankless water heater the water + solution turned inky black. I had to dump it out and switch to vinegar. Whatever small amount of HCL is in this solution is way too much for either my pump, my lines or my heater (not sure where the damage occurred). This is NOT a good solution for tankless descaling.
Rating: 1 stars