For my Zettelkasten I use Obsidian (see docu - Obsidian) as editor and document organizer. This way, each page (or Zettel) is written and formatted in markdown (see docu - Markdown). This also allows to include page-links and hashtags to connect thoughts to each other. The rules, with which I connect individual pages are described here: Connection Rules for Zettels
Also I’d like to publish my Zettelkasten some day in form of a digital garden (see Digital Garden - Publishing Zettelkasten to the web)