Let it boil for a bit (no dairy so no worries of scalding). Bring to a simmer. It will eventually tighten up after about 20 minutes (I didn't time it, but it's a rough guess). If you want to force it to tighten up you can add the psyllium husk (but forewarned, it will turn the soup into a literal almost 'gelatin' like state if your too heavy handed).