throw the salifert alk test out. It reads WAY higher then EVERY other brand (about 2dKH give or take a few fractions). go get a few more test kits (API, ELOS, Aquarium systems, Seachem, high dollar or low dollar ect). I'll put my last dollar they all read about the same except the salifert. Dont ask me why, its always been like that. several other people have noticed in back to back testing. I wouldn't assume the salifert in this case is right just because of its prestige. In this case I dont trust salifert (not that I trust redsea either but I know salifert has read high in the past).