I had been using fritz rpm on my new tank and shooting for 8-8.2 kh, which I had no problem with for the first 9 months of the tank. I opened a new box and after a water change had an alk spike up to 9+, and after testing with a red sea kit I found it had an alk of almost 11! Not wanting to keep my alk that high or cause swings with every water change, I decided to switch to red sea blue bucket for it's stated 8 kh at 35 ppt salinity. However, much to my dismay, I tested my first batch and it came back with an alk of 9.4 on my red sea kit. I began to think my alk reagent had gone bad, so I ordered a hanna alk tester, but when I mixed up a new batch yesterday for my second water change, both the hanna and the red sea kit are reading around 9.4. When I check the batch # it says the alk of this batch is only 7.75 dkh, and calcium and mag both test dead on to what the batch # icp tested at. I'm very confused and trying to slowly bring down alk to at least 8.5 (I'd like it at 8 ideally) by turning off my kalk doser for a few days is definitely causing problems with my few sps frags. Has anyone else had this problem? I had my alk rock solid until all of this and everything was doing great at 8 kh. Now I feel like I've wasted 120$+ on 2 boxes of salt that are not giving me a correct alk.