Nothing is really standard. I created a tag same as my music account and used to use it for my music posts. I also had the idea for others to use it so post discovery would be easier for me. But after one time mentioning this in a post, never really expanded on it. Basically what I try to tell, use the tags like you want to do it. Manual curators generally look at the main tags; for music this is #music but other tags are out there as well.