I need to drop it around 1 meq/L. I have been using aquavitro salt, doing 20 gallon water changes on a 75 gallon tank with a 30 gallon sump. My tank seems to do better around 2.6-2.8 meq/L instead of the 3.2-3.8 meq/L that the aquavitro seems to mix at. I will be switching salts after I get done with these two buckets I am currently working on, but that may be a while. I have no problem finding muriatic acid, but worry about impurities and if I don't need to work with a strong acid, I would feel much better. Thoughts?