I don't recommend dosing anything if I don't have a test kit for it. I have seen people wipe out invertebrates by doing a dosing regimen with Iodine.
I dose a 2 part Calcium and Alkalinity product called B-Ionic. I also drip Kalk often. However, I didn't do that until I owned test kits for Alkalinity, pH, and Calcium.
Choosing a Calcium and Alkalinity Scheme
and here's another one of my favorites.
Solving Calcium and Alkalinity Problems
Most trace elements are replaced when doing a waterchange.