Any info on the uses of these chemicals would be appreciated. Putting smaller eyedroppers in the bottles might help. Boric acid is also used as a buffer in acid plating baths. Elemental fluorine is not used, but hydrofluoric acid and fluoboric acids and acid salts are widely used. Sorry, I'm not familiar with barium sulphide.
Boric acid is a wonderful buffer for plating baths.
Hplus ion is frequently removed from the difussion zone which is possibly a millionth of an inch thick on the part that you are plating. Boric acid has 3 hydrogen ions that will come out as required to maintain a pH on the surface. They come out at 3 different pH's, so are wonderfully useful in lots of different plating solutions. It has a tendancy to make the plate white or bright, this is because it maintains the pH very well. Higher ph's tend to give a dark or even black look that is sometimes rough.