So lets say I have some plant material with DMT. I do several acid baths, or maybe with just plain water. Then I evaporate the water. As I evaporate gunk appears on the surface. It gets stuck on the sides of the pan. I change to smaller pots as I go along so I lose the gunk there. Perhaps I lose it when I filter. Does this gunk contain significant amounts of DMT, or does DMT only precipitate out of water when there is very little water and relatively a lot of DMT?

If I knew more chemistry perhaps this answer would be as simple as knowing whether a molecule's solubility is effected by other solutes. But then even that's not simple is it?

It's a hard question even for a chemist to answer theorically because solubilities in complex mixtures is...well... complex.. You dont have just DMT and a clean solvent, you have many other things which affect solubility, so it's hard to say what will precipitate before.

But what I can say is that there was one published paper (forgot source but I can look it up if necessary) that tested ayahuasca which had some precipitation and both the precipitation as well as the liquid tested positive for alkaloids. Or by personal experience, drinkign the gunk on the bottom of ayahuasca is definitely active (though strong tasted) Hence why people tell you to avoid filtering AFTER reducing, it's best to filter only before filtering. There are better ways to clean up a brew I think.

Ok, that answers my question perfectly. I'm the middle of an extraction where I did exactly the un-recommended filtering after reducing, but I've saved the gunk I filtered out so hopefully I'll pick up any dmt in there on the next extraction. I suppose its all about the defatting, washing, and re-xing.