Ur ok bro lol!!
Dosing is considered a liquid form of Alk, Calcium, Magnesium, Strontium... etc, etc, to help stabilize your tank parameters. Having a consistant and stable tank with help in coral development. As mentioned earlier some people dose Vodka as a carbon source to help combat Nitrate and Phosphate issues which hinder coral development. Thus they dose Vodka or Sugar.
Chemipure and purigen are not considered dosing as they are solids. I've never used them so I can not tell you more about them. I just let my tank cycle without any use for chemicals.
Next meeting is in April.... so stay tuned.