Every week when I do my water change my dkh goes up about 3 points every time. I test every other day and usually my alk is about 10.5 the day before water change and after it goes up to 12.5~. I use instant ocean reef crystals. Anybody else have this problem? I don’t dose anything for alk or calcium because it’s already so high. I use Red Sea test kits. Any recommendations for new salt?